Question: A similar question was asked [here](http://social.msdn.microsoft.com/Forums/en/msbuild/thread/9d2e32c2-09bc-445d-9c0c-e5b75b808b34) without any answers. I have a cs project with a reference to MySql.Data.Dll with CopyLocal=true. When I run the msbuild from command line on one computer (Windows 7 64 bit), it works perfectly.

When I run the same MsBuild on another computer (Windows Server 2008 RC2), the DLL is not copied to the output directory. Other copy-local DLLs are copied without a problem, and no error is printed. I do have permissions to access the DLL, and copying it manually works. 

Does anyone know why this happens / how to circumvent?

Answer: 
MySql.Data.Dll may be in the GAC on the Win 2008 RC2 computer and not on the Win7 one, which could explains the different behaviours.
It may not be relevant, but I saw a similar problem to this when I moved a dll out to be handled by a project reference. It'd build fine locally, but wouldn't copy the dll over on the TFS machine. Turns out I had to remove the original reference to the dll itself in the csproj so it knew to copy it over via the project reference.

I can't remember much more about the problem though so it's not much of an answer.