Outlook PST file error

[superrid]

I have a fairly large PST file (>5G) that has become corrupted. (I am using Outlook 2007.) When I try to open it, Outlook says it isn't a PST file. When I scan it with SCANPST, it recognizes it, scans it, and attempts to repair it. (SCANPST says it fixes it, but I have scanned the file about 10 times, and it comes up with the same errors each time in the log.)

Can anyone help with a recommendation on how to fix it?

 

[Osiris]

what is the file extention on it? Does it say example.pst or does it say example.file?

 

[superrid]

The name of the file is inbox.pst.