A client had a problem with the Rules and Alerts dialog. When he attempted to open it, it flashed on the screen for a split second then disappeared. It worked fine in a second profile that only had one email account, but not in his main profile with three accounts.
I learned two of the three email accounts were shared mailboxes that were automapped to his mailbox, but which he added to his profile as separate accounts. I used PowerShell to set AutoMapping to False and voila, Rules and Alerts opened once again.