We were unable to establish the connection because it is configured for user olduser@old.com but you attempted to connect using user newuser@new.com. To connect as a different user perform a switch user operation. To connect with the configured identity just attempt the last operation again.

1. Close Visual Studio
2. Start the Developer Command prompt installed with Visual Studio as an administrator.
3. type 'devenv /resetuserdata' ('wdexpress /resetuserdata' for Express SKUs)
4. Start Visual Studio Normally.