How do I unmap a project?

Solution 1:

You should be able to go to Workspaces and remove/add any mappings there directly.

1. Go To Source Control Explorer
2. Expand the Workspaces drop-down along the toolbar in the Source Control Explorer
3. Click the last entry to manage workspaces

There you should be able to remove mappings.

Here is an article discussing Workspaces
http://www.woodwardweb.com/teamprise/000334.html

Solution 2:

I would like to add something to the accepted response...

If you have used some other credential to get code previously, then there would be a workspace already existing that would be mapped to the mentioned local folder. In that case the new credential can not be used to map the same server folder to the same local folder. You will first have to login with the older credential and delete that workspace and then you need to create a new workspace with your new ID and then map to the desired folder (which should now be unlocked) and you should be ready to go.