This is an interested blog from a Microsoft escalation engineer – Eric Norberg posted on his Technet blog:
If you suspect you might have a problem with a corrupted OOF, you’ve followed all of the troubleshooting steps that you can think of and aren’t getting anywhere, have a look at Eric’s blog. ..Eric troubleshoots the issue with MFCMAPI and steps through a theoretical example but as he mentions this would be last resort.
..and another thing - Why is OOF an OOF and not an OOO?
“OOF was a command used in the days of Microsoft’s Xenix mail system, which set a user as ‘Out of Facility’ – i.e. Out of the Office”
..and by the power of Live search…