There is no EventLog source named "ASP.NET 4.6.81.0". This module requires .NET Framework 2.0

The answers above are correct for the point, however the suggested fix is ​​not perfect.

The UnhandledExcepton module is the third piece of code that is sourced from CodePlex . The goal is to catch exceptions that aren't being handled and log them somewhere. This can be useful, so deleting is not really the answer to this problem.

Also, creating the "ASP.NET 4.6.81.0" event log source is not actually a fix. This may cause you to lose the problem shown here, but it will most likely break again the next time you update the .NET framework.

If you look in the source code, you can see that the module uses the assembly version (WebEngine.dll) that ships with the .NET framework to find the name of the event log source to use. The file can be found in the runtime directory, which will depend on the framework version and "bitness". eg

C:\Windows\Microsoft.NET\Framework\v4.0.30319\WebEngine.dll

      

        
        
        
      

    

Violation code:

string webenginePath = Path.Combine(RuntimeEnvironment.GetRuntimeDirectory(), "webengine.dll");

      

        
        
        
      

    

and

FileVersionInfo ver = FileVersionInfo.GetVersionInfo(webenginePath);
sourceName = string.Format(CultureInfo.InvariantCulture, "ASP.NET {0}.{1}.{2}.0", ver.FileMajorPart, ver.FileMinorPart, ver.FileBuildPart);

      

        
        
        
      

    

If this log source does not exist, an error occurs.

The reason this is happening now is because .NET 4.6 is replacing .NET 4.5 and not side-by-side. The installation replaced the WebEngine.dll file with the new version 4.6.81.0. The previous version in .NET 4.5.2 was 4.0.30319 (which matched the CLR version).

There is no event log source for " AP.NET 4.6.81.0

", hence an error.

The original author of the UnhandledException module should use code that returns the CLR version and not rely on the file version.

eg.

System.Environment.Version

Major  Minor  Build  Revision
-----  -----  -----  --------
4      0      30319  34209

      

        
        
        
      

    

If the string that was looking for the environment version used this instead, it will continue to work with the 4.6 framework. Of course, this does not guarantee that it will continue to work in later versions, however it would be a safer choice than file versions.

So the answer is to change the code in the UnhandledExceptionModule to do this, recompile it, and update your references accordingly.

eg.

_sourceName = string.Format(CultureInfo.InvariantCulture, "ASP.NET {0}.{1}.{2}.0",System.Environment.Version.Major, System.Environment.Version.Minor, System.Environment.Version.Build);

      

        
        
        
      

    

UPDATE 2015-DEC-04: I fixed this issue and uploaded a new version of the offending class to the original codeplex site. The original author does not seem to be active on the site and so I do not expect the patch to be merged into the original control, but it is available to everyone. See the issue for a description of the issue and the associated patch