As another MS tech suggested the problem could lie in the registry.
See if you can learn from some friend what's the exact version of the Campus NAV you had installed. Norton 360 for instance doesn't use the same removal tool as the other versions.
Start in safe mode with your older account and make sure everything is unticked there under services (hide non-ms services) and startup. Then restart and see if you can log normally with your old account.
I'm not a big fan of registry cleaners, but see if
ccleaner finds anything. Just report what it finds, don't remove anything yet. You can already make a complete backup of your registry with
erunt.
I've asked some help from other staffers, maybe they'll come up with something.