Microsoft Outlook: “the account you have added is not fully configured” error

I recently discovered a fix for the rare but annoying “the account you have added is not fully configured” when attempting to add an Exchange mailbox in Outlook 2003. I discovered it by mentioning it to a co-worker who happened to know about this rare issue– which is not documented anywhere that I searched (brief Google search including Microsoft KB or Experts Exchange). I probably didn’t give it my best effort, but nonetheless, the fix was incredibly simple.

The fix is to search for mapisvc.inf and delete both instances (windows/system32 and program files/common files), then re-create the Outlook profile which will be wiped out as a result.