Is it possible to run a NET 4 5 app on XP

Question

First  I have read the following    Connect case VS case and especially this channel9 post   So  from the last bullet  I really think there is no way around this  but I had to see if I could get a definitive answer as my team would like to upgrade from  NET 4 0 to  NET 4 5  However  we have to support XP   Is there no possibility of going to  NET 4 5 if we want to support XP   The only thing I could think of is creating two separate solutions  but then the codebases would have to diverge if we used  NET 4 5 features   So  I am looking for some amazing workaround that I could not find and others maybe already know

User · Answer

Last version to support windows XP  SP3  is mono-4 3 2 467-gtksharp-2 12 30 1-win32-0 msi and that doesnot replace  NET 4 5 but could be of interest for some applications   see there  https   download mono-project com archive 4 3 2 windows-installer

User · Answer

I hesitate to post this answer  it is actually technically possible but it doesn t work that well in practice   The version numbers of the CLR and the core framework assemblies were not changed in 4 5   You still target v4 0 30319 of the CLR and the framework assembly version numbers are still 4 0 0 0   The only thing that s distinctive about the assembly manifest when you look at it with a disassembler like ildasm exe is the presence of a   TargetFramework  attribute that says that 4 5 is needed  that would have to be altered   Not actually that easy  it is emitted by the compiler   The biggest difference is not that visible  Microsoft made a long-overdue change in the executable header of the assemblies   Which specifies what version of Windows the executable is compatible with   XP belongs to a previous generation of Windows  started with Windows 2000   Their major version number is 5   Vista was the start of the current generation  major version number 6    NET compilers have always specified the minimum version number to be 4 00  the version of Windows NT and Windows 9x   You can see this by running dumpbin exe  headers on the assembly   Sample output looks like this   OPTIONAL HEADER VALUES              10B magic    PE32                              4 00 operating system version             0 00 image version             4 00 subsystem version                  lt     here                  0 Win32 version                   What s new in  NET 4 5 is that the compilers change that subsystem version to 6 00   A change that was over-due in large part because Windows pays attention to that number  beyond just checking if it is small enough   It also turns on appcompat features since it assumes that the program was written to work on old versions of Windows   These features cause trouble  particularly the way Windows lies about the size of a window in Aero is troublesome   It stops lying about the fat borders of an Aero window when it can see that the program was designed to run on a Windows version that has Aero   You can alter that version number and set it back to 4 00 by running Editbin exe on your assemblies with the  subsystem option   This answer shows a sample postbuild event   That s however about where the good news ends  a significant problem is that  NET 4 5 isn t very compatible with  NET 4 0   By far the biggest hang-up is that classes were moved from one assembly to another   Most notably  that happened for the  Extension  attribute   Previously in System Core dll  it got moved to Mscorlib dll in  NET 4 5   That s a kaboom on XP if you declare your own extension methods  your program says to look in Mscorlib for the attribute  enabled by a  TypeForwardedTo  attribute in the  NET 4 5 version of the System Core reference assembly   But it isn t there when you run your program on  NET 4 0  And of course there s nothing that helps you stop using classes and methods that are only available on  NET 4 5   When you do  your program will fail with a TypeLoadException or MissingMethodException when run on 4 0  Just target 4 0 and all of these problems disappear   Or break that logjam and stop supporting XP  a business decision that programmers cannot often make but can certainly encourage by pointing out the hassles that it is causing   There is of course a non-zero cost to having to support ancient operating systems  just the testing effort is substantial   A cost that isn t often recognized by management  Windows compatibility is legendary  unless it is pointed out to them   Forward that cost to the client and they tend to make the right decision a lot quicker     But we can t help you with that

User · Answer

Try mono   http   www go-mono com mono-downloads download html  This download works on all versions of Windows XP  2003  Vista and Windows 7

User · Answer

Sadly  no  you can t run 4 5 programs on XP   And the relevant post from that Connect page      Posted by Microsoft on 23 03 2012 at 10 39   Thanks for the report  This behavior is by design in  NET Framework 4 5 Beta  The minimum supported operating systems are Windows 7  Windows Server 2008 SP2 and Windows Server 2008 R2 SP1  Windows XP is not a supported operating system for the Beta release

User · Answer

The Mono project dropped Windows XP support and  forgot  to mention it  Although they still claim Windows XP SP2 is the minimum supported version  it is actually Windows Vista   The last version of Mono to support Windows XP was 3 2 3

[c#] Is it possible to run a .NET 4.5 app on XP?

Examples related to c#

Examples related to .net

Examples related to .net-4.0

Examples related to compatibility

Examples related to .net-4.5