If you get an HTTP 404 not found error when connecting to TFS
Delete all the files in this folder
You also may receive an error message in the VS 2013 output window, reading as follows...
We were unable to automatically populate your Visual Studio Online accounts.
The following error was encountered: One or more errors occurred.TF205020: Could not connect to server ‘tfs.russellreynolds.com\DefaultCollection’. This server was used in your last session, but it might be offline or unreachable. Confirm that the server is available on the network. To attempt to connect again, or to a different server, click ‘Connect To Team Foundation Server’ in Team Explorer or the Team menu.
The server returned the following error: HTTP code 404: Not Found