CompileWorkflowTask

When building a VS2008 solution using TFS TeamBuild 2010 the CompileWorkflowTask throws the error:

Using "CompileWorkflowTask" task from assembly "System.Workflow.ComponentModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35". Task "CompileWorkflowTask" (TaskId:631) C:\Program Files (x86)\MSBuild\Microsoft\Windows Workflow Foundation\v3.5\Workflow.Targets(127,5): error : The type 'System.Func'开发者_如何学运维 exists in both 'c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll' and 'c:\Windows\Microsoft.NET\Framework\v4.0.30319\mscorlib.dll'

I've both VS2008 and VS2010 installed on this buildserver. Any idea why this error occurs?

This is a known issue. TFS Build 2010 uses WF 4.0, so those assemblies are loaded and that's what your references are resolving to. There's a hot fix planned for this issue.