I have a client with Outlook 2013. If you schedule an appointment with a reminder then delete it, it will freeze Outlook to where your have to run the Task Manager to kill it.
I have tried:
-Running the Repair utility on MS Office
-Looking for Microsoft Update KB2553248 to uninstall it - not installed
-Turning off the Chime
There are only 3 COM Add-ins:
-ACT (contact manager software)
FYI: Client is using a single email account set as POP
The weird thing is if the appointment is set in ACT (ACT syncs to Outlook) that appointment can be deleted without issue.