All was working fine on a SBS2003 network and the user in question has outlook 2007 on their physical machine.
They tried imported a very old PST file into Outlook and it appeared to cause Outlook to hang. At which point they shutdown the computer, and as it hung on shutdown, they forced it off.
Since then outlook has crashed almost instantly when Outlook was opened. We told them to do a detect and repair on office to no avail. They then uninstalled office and reinstalled again to no avail.
We created a fresh profile that seemed to work for a short while 3-5 minutes and then crashed the same as before.
We asked them to use a different PC running Outlook 2003 and again the same result, crashes Outlook when syncing the mailbox.
We then put it down to an issue with the users mailbox, and remote dismounted the exchange database, Backed it up, Ran a defrag, Backed up again, Ran an integrity check followed by a repair. None of which seemed to report any issues, but their overall database was reduced from a mere 6GB to 4.2GB after Defrag.
The Users mailbox, accounts for a bit less than 2GB's of that space.
The user has recreated their profile "with cached exchange mode Off (read it on another post that had similar problem)" and still the same thing has happened.
I'm at a loss as to what to do next as currently the user is forced to use Exchange Web Access and wants their Outlook access restored Yesterday...