A couple of customers reported problems when using the Source Control feature in VS.NET 2005 of Team Foundation Server to check in files.
The MCMS product team has investigated this issue and identified this as a design limitation. MCMS 2002 was not designed to work with Team Foundation Server. MCMS 2002 was released several years earlier than TFS. Adding integration support at this stage would involve substantial code revision, representing a scope of risk that exceeds that which is suitable for a hotfix.
CMS and TFS can be used independently when they are both installed. However, the two products cannot be used together.
919913 – Error message when you try to use Visual Studio 2005 Team Foundation Server to check in files on a computer that is running Content Management Server 2002: “Unable to cast object of type”
See here for a workaround: