Outlook 2000 Personal Folders Gone

When my boss login to the SBS2003 server on his laptop this morning,a prompts says that a certain file was corrupted. Not knowing what to do, he press OK to proceed and so WinXP recreate another new users profile.

So I decided to open up MS Outlook 2000 to have a look, it was empty. So I went in to Control Panel->Mail and join him back to the MS Exchange.
Inside Outlook, all emails on the server was still there, but all his personal folders was gone.

I went back to his old profile inside Documents & Settings, look under Application->Microsoft->Outlook and cannot find any .pst file.

Can anyone help and advise where the folders would have been?

Thanks!