Ever since I upgraded to 2012 P&ID i keep getting a popup window that says "Exception of type 'System.Exception' was thrown." It show's up when I open most of my drawings and it will also show up when I do diferent things in the drawing. If I try to project audit to remove tags that don't exist it stops the audit with that error. This didn't start until I upgraded to 2012 P&ID.
I just discovered that on top of that I can't publish anything!!! When I try that same error comes up and stops the publish!!!
Have you tried to reinstall and just do a repair yet?
Are you running the project on your local computer or on a network drive?