I have on occasion needed to recover some emails from a PST file that have been deleted but the space has not been reclaimed and compacted.

When deleting an email in a PST file, it is only marked as gone and Outlook will ignore it, unless you then choose to compact the space as well.

There is a trick you can do however to recover these deleted emails by wiping out some hex values near the begining of the PST file and then doing a PST Repair on it.

Not everyone is happy however to use a hex editor to edit these values, so I wrote a tool to do this, it's easy enough, just run it and click start, then find your PST file. Outlook needs to be closed first however or it won't work.

It changes bytes 7 through to 13 and replaces them with hex(20) which is the space bar. Once this is done you would then need to run SCANPST.exe that should have come with your install of Outlook.