If you want to remove a team project from Team Foundation Server when the project is no longer required, you can use the TFSDeleteProject command line tool. This tool can also be used if there are components that remain undeleted after an unsuccessful team project creation.
TFSDeleteproject [/q] [/force] [/excludewss] /collection:URL TeamProjectName
You can find the TFSDeleteProject command-line tool in Drive:\Program Files\Microsoft Visual Studio 10.0\Common7\IDE on any client computer that runs Team Explorer.
Remark: TFSDeleteProject permanently destroys the team project, after which it cannot be recovered. You should backup all important project data before using TFSDeleteProject.