Error TF31004 connecting VS2012 to TFS

Error TF31004 connecting VS2012 to TFS

I am trying to setup a new connection to TFS with VS2012. Early on I was
able to add my TFS server and, using the Microsoft Git Provider, clone a
copy of the remote repository from within Visual Studio. Later, as I was
fiddling with things in Team Explorer trying to find the branch I wanted
to use, something broke. My local repository remains, but my connection to
the remote repository was somehow corrupted, as evidenced with this error:
TF31004: Unexpected error encountered while connecting to Team Foundation
Server at http: //my.server.com:8080/tfs. Wait a few minutes and try
again. If the problem persists, contact the server administrator ok help
Things I have tried to resolve this:
Wait and try again (as the error message suggested).
Restart Visual Studio.
Reboot my machine.
Reboot TFS server.
Use system restore to revert back before I installed msysgit and Microsoft
Git Provider, or had attempted to connect to the TFS server.
Review the MSDN help for the error (see below).
Search Stack Overflow (found one other related issue but did not seem to
apply).
The help page offers these tidbits, but none of them seem likely given
that I had, as I said, the connection working at one point:
The version of Team Foundation running on the local computer does not
match the version running on the Team Foundation Server server {name}.
The server returned HTML content instead of XML content.
The required Web service on the server could not be found.
Any ideas would be appreciated!