The located assembly s manifest definition does not match the assembly reference

Question

I am trying to run some unit tests in a C  Windows Forms application  Visual Studio 2005   and I get the following error   System IO FileLoadException  Could not load file or assembly  Utility  Version 1 2 0 200  Culture neutral  PublicKeyToken 764d581291d764f7  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040    at x Foo FooGO   at x Foo Foo2 String groupName   in Foo cs line 123 at x Foo UnitTests FooTests TestFoo   in FooTests cs line 98   System IO FileLoadException  Could not load file or assembly  Utility  Version 1 2 0 203  Culture neutral  PublicKeyToken 764d581291d764f7  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040   I look in my references  and I only have a reference to Utility version 1 2 0 203  the other one is old   Any suggestions on how I figure out what is trying to reference this old version of this DLL file  Besides  I don t think I even have this old assembly on my hard drive  Is there any tool to search for this old versioned assembly

User · Answer

A general answer to this kind of issue is to use binding redirects as in other answers. However, that's only part of the problem - you need to know the correct version of the assembly file that you're using. Windows properties is not always accurate and nuget is also not always accurate.

The only way to get correct version info is to analyse the file itself. One useful tool is dotPeek. The assembly name listed in dotPeek is always accurate in my experience.

So for example, the correct binding for this file is the following:

<dependentAssembly>
    <assemblyIdentity name="System.ComponentModel.Annotations" publicKeyToken="b03f5f7f11d50a3a" culture="neutral"/>
    <bindingRedirect oldVersion="0.0.0.0-4.2.1.0" newVersion="4.2.1.0"/>
</dependentAssembly>

Windows explorer says the file is 4.6.26515.06, nuget says its a 5.0.0.0 file. dotPeek says it is 4.2.1.0 and that is the version that works correctly in our software. Also note that the public key and culture are important and dotPeek also show this information.

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The question has already an answer  but if the problem has occurred by NuGet package in different versions in the same solution  you can try the following   Open NuGet Package Manager  as you see my service project version is different than others   Then update projects that contain an old version of your package

User · Answer

I ran into this issue while using an internal package repository   I had added the main package to the internal repository  but not the dependencies of the package   Make sure you add all dependencies  dependencies of dependencies  recursive etc to your internal repository as well

User · Answer

I am going to blow everyone s mind right now        Delete all the  lt assemblyBinding gt  references from your  config file  and then run this command from the NuGet Package Manager console   Get-Project -All   Add-BindingRedirect

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This question is quite old  and I had the same error message recently with Azure DevOps Yaml pipelines and Dotnet Core 3 1  The problem was somewhat different than the other answers try to solve  so I will share my solution  I had a solution with many projects for my own nuget packages  I had by accident added version-tag in the   csproj files like this     lt Project Sdk  quot Microsoft NET Sdk quot  gt     lt PropertyGroup gt       lt Version gt 1 0 0 lt  Version gt     lt  PropertyGroup gt   I packed the nuget packages for all projects using Yaml with a DotnetCoreCLI 2 task   - task  DotNetCoreCLI 2    displayName   pack     inputs       command  pack      nobuild  true      configurationToPack   Release       includesource  true      includesymbols  true      packagesToPack   MyNugetProject1 csproj    MyNugetProject2 csproj       versioningScheme   byEnvVar       versionEnvVar   GitVersion SemVer   The problem was that the version in the   csproj files didn t match the version in the environment variable GitVersion SemVer  specified by input- quot versionEnvVar quot    After removing all  lt Version gt 1 0 0 lt  Version gt -tags in the   csproj files the assembly fileversion for dll was automatically assigned by the environment-variable and both nuget and dll  assembly fileversion  would have the same version and problem was solved

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I was getting       Could not load file or assembly  XXX-new  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040    It was because I changed the name of the assembly from XXX dll to XXX-new dll  Reverting name back to the original fixed the error

User · Answer

In your AssemblyVersion in AssemblyInfo cs file  use a fixed version number instead of specifying    The   will change the version number on each compilation  That was the issue for this exception in my case

User · Answer

Had similar issue mentioned at this post  quot Any suggestions on how I figure out what is trying to reference this old version of this DLL file  quot  Needed which assembly still refers old ODATA client 6 15 0   the ildasm helped to narrow down for me  without base code access  only via deployed pkg at server   Screen shot below for quick summary  DeveloperPackge if don t have ildasm exe https   www microsoft com net download visual-studio-sdks

User · Answer

For us  the problem was caused by something else  The license file for the DevExpress components included two lines  one for an old version of the components that was not installed on this particular computer  Removing the older version from the license file solved the issue    The annoying part is that the error message gave no indication to what reference was causing the problems

User · Answer

Right click the reference in VS set  Specific Version  property to True

User · Answer

Try adding whatever s missing to the global assembly cache

User · Answer

This question is quite old  and I had the same error message recently with Azure DevOps Yaml pipelines and Dotnet Core 3 1  The problem was somewhat different than the other answers try to solve  so I will share my solution  I had a solution with many projects for my own nuget packages  I had by accident added version-tag in the   csproj files like this     lt Project Sdk  quot Microsoft NET Sdk quot  gt     lt PropertyGroup gt       lt Version gt 1 0 0 lt  Version gt     lt  PropertyGroup gt   I packed the nuget packages for all projects using Yaml with a DotnetCoreCLI 2 task   - task  DotNetCoreCLI 2    displayName   pack     inputs       command  pack      nobuild  true      configurationToPack   Release       includesource  true      includesymbols  true      packagesToPack   MyNugetProject1 csproj    MyNugetProject2 csproj       versioningScheme   byEnvVar       versionEnvVar   GitVersion SemVer   The problem was that the version in the   csproj files didn t match the version in the environment variable GitVersion SemVer  specified by input- quot versionEnvVar quot    After removing all  lt Version gt 1 0 0 lt  Version gt -tags in the   csproj files the assembly fileversion for dll was automatically assigned by the environment-variable and both nuget and dll  assembly fileversion  would have the same version and problem was solved

User · Answer

Try removing the assembly refernce from your webConfig appConfig   lt dependentAssembly gt           lt assemblyIdentity name  quot System IO quot  publicKeyToken  quot B03F5F7F11D50A3A quot  culture  quot neutral quot    gt           lt bindingRedirect oldVersion  quot 0 0 0 0-4 1 2 0 quot  newVersion  quot 4 3 0 0 quot    gt         lt  dependentAssembly gt

User · Answer

You can do a couple of things to troubleshoot this issue  First  use Windows file search to search your hard drive for your assembly   dll   Once you have a list of results  do View- Choose Details    and then check  File Version   This will display the version number in the list of results  so you can see where the old version might be coming from   Also  like Lars said  check your GAC to see what version is listed there  This Microsoft article states that assemblies found in the GAC are not copied locally during a build   so you might need to remove the old version before doing a rebuild all   See my answer to this question for notes on creating a batch file to do this for you   If you still can t figure out where the old version is coming from  you can use the fuslogvw exe application that ships with Visual Studio to get more information about the binding failures  Microsoft has information about this tool here  Note that you ll have to enable logging by setting the HKEY LOCAL MACHINE SOFTWARE Microsoft Fusion EnableLog registry key to 1

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The  NET Assembly loader    is unable to find 1 2 0 203 but did find a 1 2 0 200   This assembly does not match what was requested and therefore you get this error    In simple words  it can t find the assembly that was referenced  Make sure it can find the right assembly by putting it in the GAC or in the application path  Also see https   docs microsoft com archive blogs junfeng the-located-assemblys-manifest-definition-with-name-xxx-dll-does-not-match-the-assembly-reference

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Happened to me for System ValueTuple     Unexpected Error Could not load file or assembly  System ValueTuple    Version 4 0 1 0  Culture neutral  PublicKeyToken cc7b13ffcd2ddd51  or   one of its dependencies  The system cannot find the file specified    Solved it by installing  NET Framework 4 7 2 Runtime on the machine the error occurred on  Simple and no need to add bindingRedirect  modifying GAC or downgrading NuGet packages etc    https   dotnet microsoft com download dotnet-framework net472

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I was getting       Could not load file or assembly  XXX-new  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040    It was because I changed the name of the assembly from XXX dll to XXX-new dll  Reverting name back to the original fixed the error

User · Answer

You can do a couple of things to troubleshoot this issue  First  use Windows file search to search your hard drive for your assembly   dll   Once you have a list of results  do View- Choose Details    and then check  File Version   This will display the version number in the list of results  so you can see where the old version might be coming from   Also  like Lars said  check your GAC to see what version is listed there  This Microsoft article states that assemblies found in the GAC are not copied locally during a build   so you might need to remove the old version before doing a rebuild all   See my answer to this question for notes on creating a batch file to do this for you   If you still can t figure out where the old version is coming from  you can use the fuslogvw exe application that ships with Visual Studio to get more information about the binding failures  Microsoft has information about this tool here  Note that you ll have to enable logging by setting the HKEY LOCAL MACHINE SOFTWARE Microsoft Fusion EnableLog registry key to 1

User · Answer

The problem with me was that there were old dll s dployed that were deleted in a new build  To fix it  I just checked the box to remove additional files at destination when publishing  Remove additional files at destination

User · Answer

In my case it was an old version of the DLL in C  WINDOWS Microsoft NET Framework   Temporary ASP NET Files  directory  You can either delete or replace the old version  or you can remove and add back the reference to the DLL in your project  Basically  either way will create a new pointer to the temporary ASP NET Files

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Please run the code in Visual Studio debugger  Please run till you get the exception  There will be Visual Studio Exception UI  Please read the  full details    Show details  at the bottom of Visual Studio Exception  In Full details Show details  it told me that one of my project  which was referring to my main project has a different version  of Microsoft IdentityModel Clients ActiveDirectory   In my case  my unit test project was calling my project  My unit test project and my project has a different version of Microsoft IdentityModel Clients ActiveDirectory  I am getting run time error when my unit test were executing    I just updated the version of my unit test project with the same version of main project  It worked for me

User · Answer

If you are using Visual Studio  try  clean solution  and then rebuild your project

User · Answer

I had similar problem but no answer worked for me    The solution that worked for me was removing publicKeyToken part from project file YourProject csproj  manually   Previously it had been    lt Reference Include  Utility  Version 0 0 0 0  Culture neutral  PublicKeyToken e71b9933bfee3534  processorArchitecture MSIL  gt     lt SpecificVersion gt False lt  SpecificVersion gt     lt HintPath gt dlls Utility dll lt  HintPath gt   lt  Reference gt    After change it was    lt Reference Include  Utility  Version 1 0 1 100  Culture neutral  processorArchitecture MSIL  gt     lt SpecificVersion gt False lt  SpecificVersion gt     lt HintPath gt dlls Utility dll lt  HintPath gt   lt  Reference gt    Be sure that SpecificVersion is False

User · Answer

This exact same error is thrown if you try to late bind using reflection  if the assembly you are binding to gets strong-named or has its public-key token changed   The error is the same even though there is not actually any assembly found with the specified public key token   You need to add the correct public key token  you can get it using sn -T on the dll  to resolve the error   Hope this helps

User · Answer

In your AssemblyVersion in AssemblyInfo cs file  use a fixed version number instead of specifying    The   will change the version number on each compilation  That was the issue for this exception in my case

User · Answer

I just ran across this issue and the problem was I had an old copy of the  dll in my application debug directory   You might want to also check there  instead of the GAC  to see if you see it

User · Answer

I had similar problem but no answer worked for me    The solution that worked for me was removing publicKeyToken part from project file YourProject csproj  manually   Previously it had been    lt Reference Include  Utility  Version 0 0 0 0  Culture neutral  PublicKeyToken e71b9933bfee3534  processorArchitecture MSIL  gt     lt SpecificVersion gt False lt  SpecificVersion gt     lt HintPath gt dlls Utility dll lt  HintPath gt   lt  Reference gt    After change it was    lt Reference Include  Utility  Version 1 0 1 100  Culture neutral  processorArchitecture MSIL  gt     lt SpecificVersion gt False lt  SpecificVersion gt     lt HintPath gt dlls Utility dll lt  HintPath gt   lt  Reference gt    Be sure that SpecificVersion is False

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I had this problem after starting to use InstallShield  Even though the build order showed the installation project to be last it was building out of order   I corrected this by making every other project dependent upon it - this forced the installation to build last and thereby removed my assembly mismatching  I hope this helps

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I had this problem after starting to use InstallShield  Even though the build order showed the installation project to be last it was building out of order   I corrected this by making every other project dependent upon it - this forced the installation to build last and thereby removed my assembly mismatching  I hope this helps

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The other answers wouldn t work for me   If you don t care about the version and you just want your app to run then right click on the reference and set  specific version  to false   This worked for me

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Here s my method of fixing this issue    From the exception message  get the name of the  problem  library and the  expected  version number       Find all copies of that  dll in your solution  right-click on them  and check which version of the  dll it is      Okay  so in this example  my  dll is definitely 2 0 5022 0   so the Exception version number is wrong     Search for the version number which was shown in the Exception message in all of the  csproj files in your solution   Replace this version number with the actual number from the dll    So  in this example  I would replace this      lt Reference Include  DocumentFormat OpenXml  Version 2 5 5631 0  Culture neutral  PublicKeyToken 31bf3856ad364e35  processorArchitecture MSIL    gt        with this      lt Reference Include  DocumentFormat OpenXml  Version 2 0 5022 0  Culture neutral  PublicKeyToken 31bf3856ad364e35  processorArchitecture MSIL    gt    Job done

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Mine was a very similar situation to the post by Nathan Bedford but with a slight twist  My project too referenced the changed dll in two ways   1  Directly and 2  Indirectly by referencing a component  class library  that itself had a reference to the changed dll  Now my Visual studio project for the component 2  referenced the correct version of the changed dll  However the version number of the compnent itself was NOT changed  And as a result the install of the new version of the project failed to replace that component on the client machine   End result  Direct reference  1  and Indirect reference 2  were pointing to different versions of the changed dll at the client machine  On my dev machine it worked fine   Resolution  Remove application  Delete all the DLLS from application folder  Re-install Simple as that in my case

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Solved my issue like this with brute force   I realised I hand multiple copies of the DLL all over the solution and two different versions   Went into the solution in explorer  searched for the offending DLL and deleted all of them  Then added the references to the DLL back using the one version of the DLL

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I got stumped with this for a while  I could build and run in release  couldn t in debug due to a reference that didn t match match the manifest  I must have checked the references a hundred times  and deleted all dll s  I noticed that the generated manifest in debug and release were different    I deleted the app manifest in my project properties and it fixed the problem  This didn t include mention of the offending referenced dll s - so I don t know why this was causing a problem

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Had similar issue mentioned at this post  quot Any suggestions on how I figure out what is trying to reference this old version of this DLL file  quot  Needed which assembly still refers old ODATA client 6 15 0   the ildasm helped to narrow down for me  without base code access  only via deployed pkg at server   Screen shot below for quick summary  DeveloperPackge if don t have ildasm exe https   www microsoft com net download visual-studio-sdks

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I ll let someone benefit from my shear stupidity   I have some dependencies to a completely separate application  let s call this App1    The dll s from that App1 are pulled into my new application  App2    Any time I do updates in APP1  I have to create new dll s and copy them into App2   Well     I got tired of copying and pasting between 2 different App1 versions  so I simply added a  NEW   prefix to the dll s     Well      I m guessing that the build process scans the  bin folder and when it matches something up incorrectly  it barfs with the same error message as noted above   I deleted my  new   versions and it built just dandy

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I am going to blow everyone s mind right now        Delete all the  lt assemblyBinding gt  references from your  config file  and then run this command from the NuGet Package Manager console   Get-Project -All   Add-BindingRedirect

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In my case the problem was between the chair and the keyboard  -   Could not load file or assembly  DotNetOpenAuth Core  Version 4 0 0 0  Culture neutral  PublicKeyToken 2780ccd10d57b246  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040    Two or more different assemblies wanted to use a different version of the DotNetOpenAuth library  and that would not be a problem  Furthermore  on my local computer a web config was automatically updated by NuGet    lt dependentAssembly gt       lt assemblyIdentity name  DotNetOpenAuth AspNet  publicKeyToken  2780ccd10d57b246  culture  neutral    gt           lt bindingRedirect oldVersion  0 0 0 0-4 3 0 0  newVersion  4 3 0 0    gt       lt  dependentAssembly gt       lt dependentAssembly gt           lt assemblyIdentity name  DotNetOpenAuth Core  publicKeyToken  2780ccd10d57b246  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-4 3 0 0  newVersion  4 3 0 0    gt   lt  dependentAssembly gt    Then I realized that I had forgot to copy deploy the new web config to the production server  So if you have manual way of deploying web config  check it is updated  If you have completely different web config for production server  you have to merge these dependentAssembly section in sync after using NuGet

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After trying many of the above solutions with no fix  it came down to making sure  Auto-generate binding redirects  was turned on within your application in Visual Studio   More information on enabling automatic binding redirection can be found here  https   docs microsoft com en-us dotnet framework configure-apps how-to-enable-and-disable-automatic-binding-redirection

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I received this error message due to referencing an assembly that had the same name as the assembly I was building    This compiled but it overwrote the referenced assembly with the current projects assembly - thus causing the error   To fix it I changed the name of the project  and the assembly properties available through right-clicking on the project and choosing  Properties

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I had the same issue today which prevented me from performing Add-Migration after I made changes in Entity Framework    I had two projects in my solution  let s call them  Client  and  Data  - a class library project which held my EF models and context  The Client referenced the Data project   I had signed both projects  and then later made changes to an EF model  After I removed the signature I were able to add the migrations  and could then signed the project anew   I hope this can be useful for someone  sparing them of prolonged frustration

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This same error was surfacing for me in my Unit Tests project and resulting in some failing tests   I double-checked which version of the assembly I was using in assembly explorer and checked the contents of the runtime dependentassembly tags and realized a different version of the assembly I had been using was still being referenced there   Because this was the only directive in my tests project app config I just tried deleting the entire app config file  rebuilding the solution  and that did the trick   No more reference errors for me

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I would like to just add that I was creating a basic ASP NET MVC 4 project and added DotNetOpenAuth AspNet via NuGet  This resulted in the same error after I referenced a mismatching DLL file for Microsoft Web WebPages OAuth   To fix it I did a Update-Package and cleaned the solution for a full rebuild   That worked for me and is kind of a lazy way  but time is money -P

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The question has already an answer  but if the problem has occurred by NuGet package in different versions in the same solution  you can try the following   Open NuGet Package Manager  as you see my service project version is different than others   Then update projects that contain an old version of your package

User · Answer

Right click the reference in VS set  Specific Version  property to True

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I just ran across this issue and the problem was I had an old copy of the  dll in my application debug directory   You might want to also check there  instead of the GAC  to see if you see it

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If you ever get an error like  The located assembly s manifest definition does not match the assembly reference  and if you have updated via Project   Manage NuGet Packages and Update tab in VS  the first thing you could do is try installing another version of the package after checking versions from NuGet Gallery page and running the folowing command from Package Manager Console   PM gt  Install-Package YourPackageName -Version YourVersionNumber    Example PM gt  Install-Package Microsoft Extensions FileProviders Physical -Version 2 1 0   Although answer is not directly related to the package in question and it was asked way back  it is kind of generic  still relevant and hope it helps someone

User · Answer

Just deleting contents of your project s bin folder and rebuild the solution solved my problem

User · Answer

For us  the problem was caused by something else  The license file for the DevExpress components included two lines  one for an old version of the components that was not installed on this particular computer  Removing the older version from the license file solved the issue    The annoying part is that the error message gave no indication to what reference was causing the problems

User · Answer

You can do a couple of things to troubleshoot this issue  First  use Windows file search to search your hard drive for your assembly   dll   Once you have a list of results  do View- Choose Details    and then check  File Version   This will display the version number in the list of results  so you can see where the old version might be coming from   Also  like Lars said  check your GAC to see what version is listed there  This Microsoft article states that assemblies found in the GAC are not copied locally during a build   so you might need to remove the old version before doing a rebuild all   See my answer to this question for notes on creating a batch file to do this for you   If you still can t figure out where the old version is coming from  you can use the fuslogvw exe application that ships with Visual Studio to get more information about the binding failures  Microsoft has information about this tool here  Note that you ll have to enable logging by setting the HKEY LOCAL MACHINE SOFTWARE Microsoft Fusion EnableLog registry key to 1

User · Answer

The problem with me was that there were old dll s dployed that were deleted in a new build  To fix it  I just checked the box to remove additional files at destination when publishing  Remove additional files at destination

User · Answer

The  NET Assembly loader    is unable to find 1 2 0 203 but did find a 1 2 0 200   This assembly does not match what was requested and therefore you get this error    In simple words  it can t find the assembly that was referenced  Make sure it can find the right assembly by putting it in the GAC or in the application path  Also see https   docs microsoft com archive blogs junfeng the-located-assemblys-manifest-definition-with-name-xxx-dll-does-not-match-the-assembly-reference

User · Answer

In my case it was an old version of the DLL in C  WINDOWS Microsoft NET Framework   Temporary ASP NET Files  directory  You can either delete or replace the old version  or you can remove and add back the reference to the DLL in your project  Basically  either way will create a new pointer to the temporary ASP NET Files

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I got this error while building on Team Foundation Server s build-service  It turned out I had multiple projects in my solution using different versions of the same library added with NuGet  I removed all old versions with NuGet and added the new one as reference for all   Team Foundation Server puts all DLL files in one directory  and there can only be one DLL file of a certain name at a time of course

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I added a NuGet package  only to realize a black-box portion of my application was referencing an older version of the library   I removed the package and referenced the older version s static DLL file  but the web config file was never updated from    lt dependentAssembly gt       lt assemblyIdentity name  Newtonsoft Json  publicKeyToken  30ad4fe6b2a6aeed    gt       lt bindingRedirect oldVersion  0 0 0 0-4 5 0 0  newVersion  6 0 0 0    gt   lt  dependentAssembly gt    to what it should have reverted to when I uninstalled the package    lt dependentAssembly gt       lt assemblyIdentity name  Newtonsoft Json  publicKeyToken  30ad4fe6b2a6aeed    gt       lt bindingRedirect oldVersion  0 0 0 0-4 0 0 0  newVersion  4 5 0 0    gt   lt  dependentAssembly gt

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I just ran into this problem myself  and I found that the issue was something different than what the others have run into   I had two DLLs that my main project was referencing   CompanyClasses dll and CompanyControls dll   I was getting a run-time error saying      Could not load file or assembly    CompanyClasses  Version 1 4 1 0    Culture neutral    PublicKeyToken 045746ba8544160c  or   one of its dependencies  The located   assembly s manifest definition does   not match the assembly reference   Trouble was  I didn t have any CompanyClasses dll files on my system with a version number of 1 4 1   None in the GAC  none in the app folders   none anywhere   I searched my entire hard drive   All the CompanyClasses dll files I had were 1 4 2    The real problem  I found  was that CompanyControls dll referenced version 1 4 1 of CompanyClasses dll   I just recompiled CompanyControls dll  after having it reference CompanyClasses dll 1 4 2  and this error went away for me

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No solution worked for me  I tried clean project solution  remove bin  update package  downgrade package and so on    After two hours I loaded default App config from project with assemblies and there I changed wrong reference version from    lt dependentAssembly gt       lt assemblyIdentity name  Microsoft IdentityModel Logging  publicKeyToken  31bf3856ad364e35  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-5 5 0 0  newVersion  5 5 0 0    gt   lt  dependentAssembly gt    to    lt dependentAssembly gt       lt assemblyIdentity name  Microsoft IdentityModel Logging  publicKeyToken  31bf3856ad364e35  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-3 14 0 0  newVersion  5 5 0 0    gt   lt  dependentAssembly gt    After this I cleaned project  build it again and it worked  No warning no problem

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You can do a couple of things to troubleshoot this issue  First  use Windows file search to search your hard drive for your assembly   dll   Once you have a list of results  do View- Choose Details    and then check  File Version   This will display the version number in the list of results  so you can see where the old version might be coming from   Also  like Lars said  check your GAC to see what version is listed there  This Microsoft article states that assemblies found in the GAC are not copied locally during a build   so you might need to remove the old version before doing a rebuild all   See my answer to this question for notes on creating a batch file to do this for you   If you still can t figure out where the old version is coming from  you can use the fuslogvw exe application that ships with Visual Studio to get more information about the binding failures  Microsoft has information about this tool here  Note that you ll have to enable logging by setting the HKEY LOCAL MACHINE SOFTWARE Microsoft Fusion EnableLog registry key to 1

User · Answer

If you are using Visual Studio  try  clean solution  and then rebuild your project

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I got stumped with this for a while  I could build and run in release  couldn t in debug due to a reference that didn t match match the manifest  I must have checked the references a hundred times  and deleted all dll s  I noticed that the generated manifest in debug and release were different    I deleted the app manifest in my project properties and it fixed the problem  This didn t include mention of the offending referenced dll s - so I don t know why this was causing a problem

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Please run the code in Visual Studio debugger  Please run till you get the exception  There will be Visual Studio Exception UI  Please read the  full details    Show details  at the bottom of Visual Studio Exception  In Full details Show details  it told me that one of my project  which was referring to my main project has a different version  of Microsoft IdentityModel Clients ActiveDirectory   In my case  my unit test project was calling my project  My unit test project and my project has a different version of Microsoft IdentityModel Clients ActiveDirectory  I am getting run time error when my unit test were executing    I just updated the version of my unit test project with the same version of main project  It worked for me

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check the licenses licx in properties of project you will find the wrong version there     it worked for me in active report refrences

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I just found another reason why to get this error  I cleaned my GAC from all versions of a specific library and built my project with reference to specific version deployed together with the executable  When I run the project I got this exception searching for a newer version of the library   The reason was publisher policy  When I uninstalled library s versions from GAC I forgot to uninstall publisher policy assemblies as well so instead of using my locally deployed assembly the assembly loader found publisher policy in GAC which told it to search for a newer version

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I got the same error    In my case it got resolved as follows    At first when the application was installed then the people here had used Microsoft Enterprise Library 4 1 in the application  In previous week my machine was formatted  amp  after that today when I built that application then it gave me an error that Enterprise Library assembly is missing  Then I installed Microsoft Enterprise Library 5 0 which I got on Google as first search entry   Then when I built the application then it gave me the above error i e  The located assembly s manifest definition does not match the assembly reference  After much of a search work  amp  analysis  I found that application was referring 4 1 0 0  amp  the DLL in the bin folder was of the version 5 0 0 0 What i did was then I installed the Microsoft Enterprise Library 4 1  Removed the previous reference 5 0   amp  added the 4 0 reference  Built the application  amp  voila   it worked

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The following redirects any assembly version to version 3 1 0 0  We have a script that will always update this reference in the App config so we never have to deal with this issue again   Through reflection you can get the assembly publicKeyToken and generate this block from the  dll file itself    lt assemblyBinding xmlns  urn schemas-microsoft-com asm v1  gt    lt dependentAssembly gt       lt assemblyIdentity name  Castle Core  publicKeyToken  407dd0808d44fbdc  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-65535 65535 65535 65535  newVersion  3 1 0 0    gt     lt  dependentAssembly gt   lt  assemblyBinding gt    Note that without an XML namespace attribute  xmlns  this will not work

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I got this error while building on Team Foundation Server s build-service  It turned out I had multiple projects in my solution using different versions of the same library added with NuGet  I removed all old versions with NuGet and added the new one as reference for all   Team Foundation Server puts all DLL files in one directory  and there can only be one DLL file of a certain name at a time of course

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I ll let someone benefit from my shear stupidity   I have some dependencies to a completely separate application  let s call this App1    The dll s from that App1 are pulled into my new application  App2    Any time I do updates in APP1  I have to create new dll s and copy them into App2   Well     I got tired of copying and pasting between 2 different App1 versions  so I simply added a  NEW   prefix to the dll s     Well      I m guessing that the build process scans the  bin folder and when it matches something up incorrectly  it barfs with the same error message as noted above   I deleted my  new   versions and it built just dandy

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I got the same error    In my case it got resolved as follows    At first when the application was installed then the people here had used Microsoft Enterprise Library 4 1 in the application  In previous week my machine was formatted  amp  after that today when I built that application then it gave me an error that Enterprise Library assembly is missing  Then I installed Microsoft Enterprise Library 5 0 which I got on Google as first search entry   Then when I built the application then it gave me the above error i e  The located assembly s manifest definition does not match the assembly reference  After much of a search work  amp  analysis  I found that application was referring 4 1 0 0  amp  the DLL in the bin folder was of the version 5 0 0 0 What i did was then I installed the Microsoft Enterprise Library 4 1  Removed the previous reference 5 0   amp  added the 4 0 reference  Built the application  amp  voila   it worked

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I had the same error but in my case I was running a custom nuget package locally into another project  What fixed it for me was changing the package version to the version requested in the error  The package was in netstandard 2 1 and the project requesting the package was in netcore 3 1

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I added a NuGet package  only to realize a black-box portion of my application was referencing an older version of the library   I removed the package and referenced the older version s static DLL file  but the web config file was never updated from    lt dependentAssembly gt       lt assemblyIdentity name  Newtonsoft Json  publicKeyToken  30ad4fe6b2a6aeed    gt       lt bindingRedirect oldVersion  0 0 0 0-4 5 0 0  newVersion  6 0 0 0    gt   lt  dependentAssembly gt    to what it should have reverted to when I uninstalled the package    lt dependentAssembly gt       lt assemblyIdentity name  Newtonsoft Json  publicKeyToken  30ad4fe6b2a6aeed    gt       lt bindingRedirect oldVersion  0 0 0 0-4 0 0 0  newVersion  4 5 0 0    gt   lt  dependentAssembly gt

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My issue was copying source code to a new machine without pulling over any of the referenced assemblies    Nothing that I did fixed the error  so in haste  I deleted the BIN directory altogether  Rebuilt my source code  and it worked from then on out

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This same error was surfacing for me in my Unit Tests project and resulting in some failing tests   I double-checked which version of the assembly I was using in assembly explorer and checked the contents of the runtime dependentassembly tags and realized a different version of the assembly I had been using was still being referenced there   Because this was the only directive in my tests project app config I just tried deleting the entire app config file  rebuilding the solution  and that did the trick   No more reference errors for me

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The other answers wouldn t work for me   If you don t care about the version and you just want your app to run then right click on the reference and set  specific version  to false   This worked for me

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Here s my method of fixing this issue    From the exception message  get the name of the  problem  library and the  expected  version number       Find all copies of that  dll in your solution  right-click on them  and check which version of the  dll it is      Okay  so in this example  my  dll is definitely 2 0 5022 0   so the Exception version number is wrong     Search for the version number which was shown in the Exception message in all of the  csproj files in your solution   Replace this version number with the actual number from the dll    So  in this example  I would replace this      lt Reference Include  DocumentFormat OpenXml  Version 2 5 5631 0  Culture neutral  PublicKeyToken 31bf3856ad364e35  processorArchitecture MSIL    gt        with this      lt Reference Include  DocumentFormat OpenXml  Version 2 0 5022 0  Culture neutral  PublicKeyToken 31bf3856ad364e35  processorArchitecture MSIL    gt    Job done

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I received this error message due to referencing an assembly that had the same name as the assembly I was building    This compiled but it overwrote the referenced assembly with the current projects assembly - thus causing the error   To fix it I changed the name of the project  and the assembly properties available through right-clicking on the project and choosing  Properties

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Manually deleting the old assembly from folder location and then adding the reference to new assemblies might help

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I had the same error but in my case I was running a custom nuget package locally into another project  What fixed it for me was changing the package version to the version requested in the error  The package was in netstandard 2 1 and the project requesting the package was in netcore 3 1

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I faced the same problem while running my unit testcases   The error clearly states the problem is  when we try to load assembly  the  NET assembly loader tries to load its referred assemblies based on its manifest data  referred assembly name  public key token  version    To check manifest data    Open the Visual Studio command prompt  Type  ildasm  and drag the required assembly to the ILDASM window and open MANIFEST view  Sometimes MANIFEST contains one assembly with two versions old version as well as new version like Utility  Version 1 2 0 200 and Utility  Version 1 2 0 203   In reality  the referred assembly is Utility  Version 1 2 0 203 new version   but since the manifest contains even Utility  Version 1 2 0 200 old version    NET assembly loader tries to find out this versioned DLL file  fails to find and so throws exception    To solve this  just drag each of the project dependent assemblies to the ILDASM window separately and check which dependent assembly holds the manifest data with the old assembly version  Just rebuild this dependent assembly and refer it back to your project

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If you ever get an error like  The located assembly s manifest definition does not match the assembly reference  and if you have updated via Project   Manage NuGet Packages and Update tab in VS  the first thing you could do is try installing another version of the package after checking versions from NuGet Gallery page and running the folowing command from Package Manager Console   PM gt  Install-Package YourPackageName -Version YourVersionNumber    Example PM gt  Install-Package Microsoft Extensions FileProviders Physical -Version 2 1 0   Although answer is not directly related to the package in question and it was asked way back  it is kind of generic  still relevant and hope it helps someone

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No solution worked for me  I tried clean project solution  remove bin  update package  downgrade package and so on    After two hours I loaded default App config from project with assemblies and there I changed wrong reference version from    lt dependentAssembly gt       lt assemblyIdentity name  Microsoft IdentityModel Logging  publicKeyToken  31bf3856ad364e35  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-5 5 0 0  newVersion  5 5 0 0    gt   lt  dependentAssembly gt    to    lt dependentAssembly gt       lt assemblyIdentity name  Microsoft IdentityModel Logging  publicKeyToken  31bf3856ad364e35  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-3 14 0 0  newVersion  5 5 0 0    gt   lt  dependentAssembly gt    After this I cleaned project  build it again and it worked  No warning no problem

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In my case  this error occurred while running an ASP NET application  The solution was to    Delete the obj and bin folders in the project folder   Clean didn t work  rebuild didn t work  all references were fine  but it wasn t writing one of the libraries  After deleting those directories  everything worked perfectly

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The following redirects any assembly version to version 3 1 0 0  We have a script that will always update this reference in the App config so we never have to deal with this issue again   Through reflection you can get the assembly publicKeyToken and generate this block from the  dll file itself    lt assemblyBinding xmlns  urn schemas-microsoft-com asm v1  gt    lt dependentAssembly gt       lt assemblyIdentity name  Castle Core  publicKeyToken  407dd0808d44fbdc  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-65535 65535 65535 65535  newVersion  3 1 0 0    gt     lt  dependentAssembly gt   lt  assemblyBinding gt    Note that without an XML namespace attribute  xmlns  this will not work

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Try adding whatever s missing to the global assembly cache

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I had a similar problem when attempting to update one DLL file of my web-site   This error was occurring  when I simply copied this DLL file into bin folder over FTP   I resolved this problem by    stopping the web-site  copying needed DLL file DLL files  starting the web-site

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This exact same error is thrown if you try to late bind using reflection  if the assembly you are binding to gets strong-named or has its public-key token changed   The error is the same even though there is not actually any assembly found with the specified public key token   You need to add the correct public key token  you can get it using sn -T on the dll  to resolve the error   Hope this helps

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I faced the same problem while running my unit testcases   The error clearly states the problem is  when we try to load assembly  the  NET assembly loader tries to load its referred assemblies based on its manifest data  referred assembly name  public key token  version    To check manifest data    Open the Visual Studio command prompt  Type  ildasm  and drag the required assembly to the ILDASM window and open MANIFEST view  Sometimes MANIFEST contains one assembly with two versions old version as well as new version like Utility  Version 1 2 0 200 and Utility  Version 1 2 0 203   In reality  the referred assembly is Utility  Version 1 2 0 203 new version   but since the manifest contains even Utility  Version 1 2 0 200 old version    NET assembly loader tries to find out this versioned DLL file  fails to find and so throws exception    To solve this  just drag each of the project dependent assemblies to the ILDASM window separately and check which dependent assembly holds the manifest data with the old assembly version  Just rebuild this dependent assembly and refer it back to your project

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OK  one more answer  I previously created my app as 64 bit and changed the output path  Project Properties Build Output Output Path  accordingly  Recently I changed the app to 32 Bit  x86   creating a new output path  I created a shortcut to where I thought the compiled  exe was going  No matter what I changed about the source  it got the manifest not matching error  After about an hour of frustration  I happened to check the date time of the  exe file  saw it was old obviously referencing old  dll s  I was compiling the app into the old directory and my shortcut was referencing the newer  Changed the output path to where the  exe should go  ran the shortcut and error is gone   slaps forehead

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Solved my issue like this with brute force   I realised I hand multiple copies of the DLL all over the solution and two different versions   Went into the solution in explorer  searched for the offending DLL and deleted all of them  Then added the references to the DLL back using the one version of the DLL

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I just found another reason why to get this error  I cleaned my GAC from all versions of a specific library and built my project with reference to specific version deployed together with the executable  When I run the project I got this exception searching for a newer version of the library   The reason was publisher policy  When I uninstalled library s versions from GAC I forgot to uninstall publisher policy assemblies as well so instead of using my locally deployed assembly the assembly loader found publisher policy in GAC which told it to search for a newer version

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In my case the problem was between the chair and the keyboard  -   Could not load file or assembly  DotNetOpenAuth Core  Version 4 0 0 0  Culture neutral  PublicKeyToken 2780ccd10d57b246  or one of its dependencies  The located assembly s manifest definition does not match the assembly reference   Exception from HRESULT  0x80131040    Two or more different assemblies wanted to use a different version of the DotNetOpenAuth library  and that would not be a problem  Furthermore  on my local computer a web config was automatically updated by NuGet    lt dependentAssembly gt       lt assemblyIdentity name  DotNetOpenAuth AspNet  publicKeyToken  2780ccd10d57b246  culture  neutral    gt           lt bindingRedirect oldVersion  0 0 0 0-4 3 0 0  newVersion  4 3 0 0    gt       lt  dependentAssembly gt       lt dependentAssembly gt           lt assemblyIdentity name  DotNetOpenAuth Core  publicKeyToken  2780ccd10d57b246  culture  neutral    gt       lt bindingRedirect oldVersion  0 0 0 0-4 3 0 0  newVersion  4 3 0 0    gt   lt  dependentAssembly gt    Then I realized that I had forgot to copy deploy the new web config to the production server  So if you have manual way of deploying web config  check it is updated  If you have completely different web config for production server  you have to merge these dependentAssembly section in sync after using NuGet

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check the licenses licx in properties of project you will find the wrong version there     it worked for me in active report refrences

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In my case  this error occurred while running an ASP NET application  The solution was to    Delete the obj and bin folders in the project folder   Clean didn t work  rebuild didn t work  all references were fine  but it wasn t writing one of the libraries  After deleting those directories  everything worked perfectly

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Is possible you have a wrong nugget versions in assemblyBinding try   Remove all assembly binding content in web config   app config      lt assemblyBinding xmlns  quot urn schemas-microsoft-com asm v1 quot  gt     lt dependentAssembly gt       lt assemblyIdentity name  quot Microsoft Extensions Logging Abstractions quot  publicKeyToken  quot adb9793829ddae60 quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-3 1 3 0 quot  newVersion  quot 3 1 3 0 quot    gt     lt  dependentAssembly gt     lt dependentAssembly gt       lt assemblyIdentity name  quot Microsoft Extensions DependencyInjection quot  publicKeyToken  quot adb9793829ddae60 quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-3 1 3 0 quot  newVersion  quot 3 1 3 0 quot    gt     lt  dependentAssembly gt     lt dependentAssembly gt       lt assemblyIdentity name  quot System ComponentModel Annotations quot  publicKeyToken  quot b03f5f7f11d50a3a quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-4 2 1 0 quot  newVersion  quot 4 2 1 0 quot    gt     lt  dependentAssembly gt   lt  assemblyBinding gt    Type in Package Manager Console  Add-BindingRedirect All necessary binding redirects are generated Run your application and see if it works properly  If not  add any missing binding redirects that the package console missed

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clean and rebuild the solution might not replace all the dll s from the output directory    what i ll suggest is try renaming the folder  from  bin  to  oldbin   or  obj  to  oldobj   and then try build your silution again    incase if you are using any third party dll s those you will need to copy into newly created  bin  or  obj  folder after successful build   hope this will work for you

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This can also occur if you are using both AssemblyInfo cs with the AssemblyVersion tags and your  csproj file has  with a different value   By either matching the AssemblyInfo or removing the  section all together the problem goes away

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This can also occur if you are using both AssemblyInfo cs with the AssemblyVersion tags and your  csproj file has  with a different value   By either matching the AssemblyInfo or removing the  section all together the problem goes away

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My app config contains a   lt bindingRedirect oldVersion  1 0 0 0  newVersion  2 0 11 0   gt    for npgsql  Somehow on the user s machine  my app exe config went missing  I am not sure if it was a silly user  installer glitch  or wacked out anti-virus yet   Replacing the file solved the issue

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clean and rebuild the solution might not replace all the dll s from the output directory    what i ll suggest is try renaming the folder  from  bin  to  oldbin   or  obj  to  oldobj   and then try build your silution again    incase if you are using any third party dll s those you will need to copy into newly created  bin  or  obj  folder after successful build   hope this will work for you

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My issue was copying source code to a new machine without pulling over any of the referenced assemblies    Nothing that I did fixed the error  so in haste  I deleted the BIN directory altogether  Rebuilt my source code  and it worked from then on out

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My app config contains a   lt bindingRedirect oldVersion  1 0 0 0  newVersion  2 0 11 0   gt    for npgsql  Somehow on the user s machine  my app exe config went missing  I am not sure if it was a silly user  installer glitch  or wacked out anti-virus yet   Replacing the file solved the issue

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I had the same issue today which prevented me from performing Add-Migration after I made changes in Entity Framework    I had two projects in my solution  let s call them  Client  and  Data  - a class library project which held my EF models and context  The Client referenced the Data project   I had signed both projects  and then later made changes to an EF model  After I removed the signature I were able to add the migrations  and could then signed the project anew   I hope this can be useful for someone  sparing them of prolonged frustration

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Mine was a very similar situation to the post by Nathan Bedford but with a slight twist  My project too referenced the changed dll in two ways   1  Directly and 2  Indirectly by referencing a component  class library  that itself had a reference to the changed dll  Now my Visual studio project for the component 2  referenced the correct version of the changed dll  However the version number of the compnent itself was NOT changed  And as a result the install of the new version of the project failed to replace that component on the client machine   End result  Direct reference  1  and Indirect reference 2  were pointing to different versions of the changed dll at the client machine  On my dev machine it worked fine   Resolution  Remove application  Delete all the DLLS from application folder  Re-install Simple as that in my case

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To me the code coverage configuration in the  Local testtesttings  file  caused  the problem  I forgot to update the files that were referenced there

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The  NET Assembly loader    is unable to find 1 2 0 203 but did find a 1 2 0 200   This assembly does not match what was requested and therefore you get this error    In simple words  it can t find the assembly that was referenced  Make sure it can find the right assembly by putting it in the GAC or in the application path  Also see https   docs microsoft com archive blogs junfeng the-located-assemblys-manifest-definition-with-name-xxx-dll-does-not-match-the-assembly-reference

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After trying many of the above solutions with no fix  it came down to making sure  Auto-generate binding redirects  was turned on within your application in Visual Studio   More information on enabling automatic binding redirection can be found here  https   docs microsoft com en-us dotnet framework configure-apps how-to-enable-and-disable-automatic-binding-redirection

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To me the code coverage configuration in the  Local testtesttings  file  caused  the problem  I forgot to update the files that were referenced there

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Try removing the assembly refernce from your webConfig appConfig   lt dependentAssembly gt           lt assemblyIdentity name  quot System IO quot  publicKeyToken  quot B03F5F7F11D50A3A quot  culture  quot neutral quot    gt           lt bindingRedirect oldVersion  quot 0 0 0 0-4 1 2 0 quot  newVersion  quot 4 3 0 0 quot    gt         lt  dependentAssembly gt

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I would like to just add that I was creating a basic ASP NET MVC 4 project and added DotNetOpenAuth AspNet via NuGet  This resulted in the same error after I referenced a mismatching DLL file for Microsoft Web WebPages OAuth   To fix it I did a Update-Package and cleaned the solution for a full rebuild   That worked for me and is kind of a lazy way  but time is money -P

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I had a similar problem when attempting to update one DLL file of my web-site   This error was occurring  when I simply copied this DLL file into bin folder over FTP   I resolved this problem by    stopping the web-site  copying needed DLL file DLL files  starting the web-site

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Just deleting contents of your project s bin folder and rebuild the solution solved my problem

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OK  one more answer  I previously created my app as 64 bit and changed the output path  Project Properties Build Output Output Path  accordingly  Recently I changed the app to 32 Bit  x86   creating a new output path  I created a shortcut to where I thought the compiled  exe was going  No matter what I changed about the source  it got the manifest not matching error  After about an hour of frustration  I happened to check the date time of the  exe file  saw it was old obviously referencing old  dll s  I was compiling the app into the old directory and my shortcut was referencing the newer  Changed the output path to where the  exe should go  ran the shortcut and error is gone   slaps forehead

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The  NET Assembly loader    is unable to find 1 2 0 203 but did find a 1 2 0 200   This assembly does not match what was requested and therefore you get this error    In simple words  it can t find the assembly that was referenced  Make sure it can find the right assembly by putting it in the GAC or in the application path  Also see https   docs microsoft com archive blogs junfeng the-located-assemblys-manifest-definition-with-name-xxx-dll-does-not-match-the-assembly-reference

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Is possible you have a wrong nugget versions in assemblyBinding try   Remove all assembly binding content in web config   app config      lt assemblyBinding xmlns  quot urn schemas-microsoft-com asm v1 quot  gt     lt dependentAssembly gt       lt assemblyIdentity name  quot Microsoft Extensions Logging Abstractions quot  publicKeyToken  quot adb9793829ddae60 quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-3 1 3 0 quot  newVersion  quot 3 1 3 0 quot    gt     lt  dependentAssembly gt     lt dependentAssembly gt       lt assemblyIdentity name  quot Microsoft Extensions DependencyInjection quot  publicKeyToken  quot adb9793829ddae60 quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-3 1 3 0 quot  newVersion  quot 3 1 3 0 quot    gt     lt  dependentAssembly gt     lt dependentAssembly gt       lt assemblyIdentity name  quot System ComponentModel Annotations quot  publicKeyToken  quot b03f5f7f11d50a3a quot  culture  quot neutral quot    gt       lt bindingRedirect oldVersion  quot 0 0 0 0-4 2 1 0 quot  newVersion  quot 4 2 1 0 quot    gt     lt  dependentAssembly gt   lt  assemblyBinding gt    Type in Package Manager Console  Add-BindingRedirect All necessary binding redirects are generated Run your application and see if it works properly  If not  add any missing binding redirects that the package console missed

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I just ran into this problem myself  and I found that the issue was something different than what the others have run into   I had two DLLs that my main project was referencing   CompanyClasses dll and CompanyControls dll   I was getting a run-time error saying      Could not load file or assembly    CompanyClasses  Version 1 4 1 0    Culture neutral    PublicKeyToken 045746ba8544160c  or   one of its dependencies  The located   assembly s manifest definition does   not match the assembly reference   Trouble was  I didn t have any CompanyClasses dll files on my system with a version number of 1 4 1   None in the GAC  none in the app folders   none anywhere   I searched my entire hard drive   All the CompanyClasses dll files I had were 1 4 2    The real problem  I found  was that CompanyControls dll referenced version 1 4 1 of CompanyClasses dll   I just recompiled CompanyControls dll  after having it reference CompanyClasses dll 1 4 2  and this error went away for me

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Manually deleting the old assembly from folder location and then adding the reference to new assemblies might help

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Happened to me for System ValueTuple     Unexpected Error Could not load file or assembly  System ValueTuple    Version 4 0 1 0  Culture neutral  PublicKeyToken cc7b13ffcd2ddd51  or   one of its dependencies  The system cannot find the file specified    Solved it by installing  NET Framework 4 7 2 Runtime on the machine the error occurred on  Simple and no need to add bindingRedirect  modifying GAC or downgrading NuGet packages etc    https   dotnet microsoft com download dotnet-framework net472

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I ran into this issue while using an internal package repository   I had added the main package to the internal repository  but not the dependencies of the package   Make sure you add all dependencies  dependencies of dependencies  recursive etc to your internal repository as well

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A general answer to this kind of issue is to use binding redirects as in other answers. However, that's only part of the problem - you need to know the correct version of the assembly file that you're using. Windows properties is not always accurate and nuget is also not always accurate.

The only way to get correct version info is to analyse the file itself. One useful tool is dotPeek. The assembly name listed in dotPeek is always accurate in my experience.

So for example, the correct binding for this file is the following:

<dependentAssembly>
    <assemblyIdentity name="System.ComponentModel.Annotations" publicKeyToken="b03f5f7f11d50a3a" culture="neutral"/>
    <bindingRedirect oldVersion="0.0.0.0-4.2.1.0" newVersion="4.2.1.0"/>
</dependentAssembly>

Windows explorer says the file is 4.6.26515.06, nuget says its a 5.0.0.0 file. dotPeek says it is 4.2.1.0 and that is the version that works correctly in our software. Also note that the public key and culture are important and dotPeek also show this information.

[c#] The located assembly's manifest definition does not match the assembly reference

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