Start Outlook one time with the /cleanreminders switch.
Start->run->outlook.exe /cleanreminders.

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Milly Staples [MVP - Outlook]
Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.
After furious head scratching, mencism asked:
| When I start up outlook, it occassionally shows a message saying that
| reminders can not be shown in the reminder window b/c some are unable
| to be found. I believe this has something to do w/ reoccurring
| appointment that I have changed. Unfortunately, the situation has
| not improved when I deleted the recurring events. Any ideas?