Setting up a developer box VM and cloning it for other developers is a great way to spin up machines quickly. However if you have already connected to a TFS workspace your machines may throw an error regarding the workspace when logging on a different user and opening the client for the first time.
The TFS workspace files are cached on the client machine in the following directory.
%userprofile%\appdata\local\microsoft\team foundation\3.0\cache
The file you'll need to modify will be the VersonControl.config file.
You can rename this file to VersionControl-old.config and re-launch the AX client, this will rebuild the config file with the appropriate workspace associated to the current user.