Comment 4 for bug 666291

The immediate data fixup for this bug is to purge users without profiles::

 $ bin/debug
 >>> profiles = root['profiles']
 >>> tags = root.tags
 >>> for userid in tags.getUsers():
 ... if profiles.get(userid) is None:
 ... print 'Removing tags for missing user:', userid
 ... tags.delete(user=userid)

And then, to save any changes::

 >>> import transaction; transaction.commit()

Jim, can you do that and post the output here, please?