Actually there is a problem with FxCop and Visual Studio Achievements (with Visual Studio Professional): the FxCop assemblies can’t be loaded.

Here is a workaround (note: you have to install FxCop 10.0 – not FxCop 1.36):

x86: You have to copy all files from "C:\Program Files\Microsoft Fxcop 10.0" to "C:\Program Files\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\FxCop".

x64: You have to copy all files from "C:\Program Files (x86)\Microsoft Fxcop 10.0" to "C:\Program Files (x86)\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\FxCop".