This error message is shown when linking your database to TFS or attempting to commit or get changes. This happens when SQL Source Control can't authenticate your TFS server.

Workarounds

Delete your SQL Source Control cached credentials file

1. Close SSMS.
2. Go to the SQL Source Control config files folder. By default, this is located at %localappdata%\Red Gate\SQL Source Control 4

3. Delete Credentials.XML.

4. Restart SSMS and link the database again. SQL Source Control should prompt for credentials.

Delete your cached credentials

1. Close SSMS.
2. In Control Panel, go to Credential Manager (or Network Credentials, depending on your version of Windows).
3. Remove your TFS credentials.
4. Restart SSMS and link the database again. SQL Source Control should prompt for credentials.

Manually create TFS credentials

1. Close SSMS.
2. In Control Panel, go to Credential Manager (or Network Credentials, depending on your version of Windows).
3. Add a new credentials entry for your TFS sever, user name, and password.
4. Restart SSMS and link the database again. SQL Source Control should prompt for credentials.