Since you removed NULL's, I would still think there are some in a date field like verified,updated field or source field with a NULL.
It's possible there's a schema inconsistency with current PEQ schema.
Can you send me a copy of the database (I have no access to the forums/database) to
wizardportal@email.com, or upload it somewhere?
I'll fix it faster that way.
Thanks,
GeorgeS