I have numerous versions of AutoCAD installed. In this case it's Plant Design Suite 2014 with AutoCAD 2014. After I installed Service Pack 1 for AutoCAD 2014, the admin account recognizes it, so do most user accounts, but one account (mine) never does. I've uninstalled and reinstall with no success.
I think it's a registry issue, but I'm not sure where to look (under HKey_Current_User\Software\AutoDesk\AutoCAD\19.1)