After installing some power too, my VS 2010 now always run under another admin account of me. So my previous mapping of the projects are lost and I can’t check out files to the original local path. The above error occurs if I try to remap the project to the same location. After some googling these tips helps:
In VS command line, use
c:\>tf workspaces /owner:*(to show all workspace)
c:\>tf workspace /delete COMPUTER_NAME;USER_NAME (to remove the workspace)
c:\>tf workspace COMPUTER;USERNAME (this will open a GUI dialog to edit the workspace. The BEST option!)
I change my workspace to public so that any user can work on it (in case my VS switches back to my own account).