[crystal-reports-2010] Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304'

I'm using vs2010 and crystal report version 13.0.2000.0 ,system 64bit crystal report runtime 64bit. my application is running fine on development machine but when i'm deploying on server getting this error

Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304' or one of its dependencies. The system cannot find the file specified.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.IO.FileNotFoundException: Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304' or one of its dependencies. The system cannot find the file specified.

Source of error:

CR:CrystalReportViewer ID="CrystalRportViewrRegistration" runat="server" AutoDataBind="true"

and I have checked GAC assembly I didn't find log4net.dll and even in my system I have search all and tried various things like changing runtime version and uploading lo4net dll from apache but no luck.

To configure IIS to run 32-bit applications you must follow these steps:

Open IIS Go to current server – > Application Pools Select the application pool your 32-bit application will run under Click Advanced setting or Application Pool Default Set Enable 32-bit Applications to True

This solution worked for me, thanks.

I tried all of that things and it doesn't worked for me.

I Just installed SAPCrystalReport in my computer and it's working now.

I faced same issue (VS 2015), but my application is running under 32-bit application pool. So even though machine is 64-bit. I installed 32-bit installation and it works.

Ensure version for correct platform (32-bit or 64-bit) is installed. I faced same issue when installed 32-bit run-time on 64-bit machine. Installing correct one, i.e. 64-bit, resolved the issue.

For this specific error, I installed version 20 of Crystal Report and it solved my problem: https://www.tektutorialshub.com/crystal-reports/crystal-reports-download-for-visual-studio/#Service-Pack-16

You can also download the file alone using the following link https://www.nuget.org/api/v2/package/log4net/1.2.10 rename the file to .zip and extract it.

To configure IIS to run 32-bit applications you must follow these steps:

Open IIS
Go to current server – > Application Pools
Select the application pool your 32-bit application will run under
Click Advanced setting or Application Pool Default
Set Enable 32-bit Applications to True

If this option is not available to you, follow these next steps:

Go to %windir%\system32\inetsrv\
Execute the appcmd.exe tool:

Error (While using Visual Studio 2015 in win 10 64 bit machine):

Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304' or one of its dependencies. The system cannot find the file specified.

Solution: Open IIS Go to current server – > Application Pools Select the application pool your 32-bit application will run under Click Advanced setting or Application Pool Default Set Enable 32-bit Applications to True

The above solution is solved my problem. Thanks.

If you don't see log4net.dll in %systemdrive%\windows\assembly\ on the machine you are attempting to deploy it on, it is likely you haven't successfully installed the redistributable for Crystal Reports for .Net Framework 4.0

Install (or reinstall) the latest service pack from http://scn.sap.com/docs/DOC-7824 (SAP Crystal Reports, developer version for Microsoft Visual Studio Updates & Runtime Downloads)

That runtime distribution should add log4net to the GAC along with a bunch of CrystalDecisions dll's

So in general dll has to be placed in two places:

1. GAC ( can have 32 and 64 versions of dll's)
2. your project bin folder

Thus, you just need add reference to log4net.dll. (In your case 32-bit with PublicKeyToken=692fbea5521e1304)

You can achive that by

• downloading log4net.dll separately and add reference to it
• dowloading SAP crystal report SDK (32 bit) https://wiki.scn.sap.com/wiki/display/BOBJ/Crystal+Reports%2C+Developer+for+Visual+Studio+Downloads

If you are building a windows app try to build as x64 instead of Any CPU. It should work fine.