He may not necessarily have to reinstall it. He can try doing a Spotlight search for Digitunnel, and then select "show all" then delete any instance of the name or association. Also go into OS X system preferences>system accounts/users>log in items. Make sure that none of the log in items are associated with digitunnel.
I'd also go and do a basic cache etc cleaning with Onyx. Might as well fix permissions while you're at it, if you've never done so before. Can't hurt.
thanks doug, just did OS X system preferences>system accounts/users>log in items and removed digitunnel