Acrobat Professional shuts down

User is experiencing problem with new Acrobat Professional 9.1 version.
Error "Adobe Acobat 9.1 has encountered a problem and needs to close. We are sorry for inconvinience." Please see attached screen shot

This is a recurring problem. This generally happens when the user copies text from commentary from one document to another document. But it also happens from other actions. Re-installing also did not help.

Any inputs will be very helpful. Thank You.