my pm's have dissapeared

Why have all my private messages disappeared? All my incoming ones have gone but my outgoing ones are still there.

Fran, are you sure you've not deleted them?

As far as I can tell we (admin) can't do anything to a users PMs other than en mass, ie we can remove all PMs but not just those of one user so this is not something done by admin.

thanks Niall......I think someone must have been at my computer!!!