We have a ASP.Net web application running in Visual Studio 2010 that is targeting .Net 3.5. It’s being built by TFS 2010. This web application has a couple web references, so the build creates a related XmlSerializers DLL. This DLL, however, is a .Net 4.0 assembly.
When I run this web application from the build, I get the error:
Could not load file or assembly
‘BLAH_BLAH_WEB_APPLICATION_NAME.XmlSerializers’
or one of its dependencies. This
assembly is built by a runtime newer
than the currently loaded runtime and
cannot be loaded.
We are using a msbuild .proj file that was working under TFS 2008 (using the “Upgrade Template” in the Build Definition). I saw this question and this one, but those mention using a specific SGen build step. We are not. Additionally, the proposed solution involve hard-coding the path to the 7.0A SGen, which is just…ugly.
Is there a way to force the TFS 2010 build to compile this XmlSerializers DLL as a .Net 3.5 Assembly?
The root problem was an invalid value in the registry. The SDK35ToolsPath value under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSBuild\ToolsVersions\4.0 was:
However, the build server had Windows SDK version 7.1. So, I corrected the value to be:
Then XmlSerializers DLL was now using .Net 2.0.