This is an ugly error message:
Outlook popped that one out just as I was about to leave for a vacation and wanted to send alert emails to my deleted items folder while I'm out.
So what can you do? A couple of things:
This error message means that Outlook isn't going to let you look at your rules, but you can use Outlook Web Access to look at the rules list. Once you're logged in, use the Rules button on the left-hand navigation to look at the list, make changes, or delete rules.
Option 2 deletes all of your rules, so you should try option 1 first and at least refresh your memory as to what rules you may need to re-create. Here, you'll launch Outlook using the /cleanrules switch.
C:\Program Files\Microsoft Office\OFFICE11\Outlook.exe /cleanrules