Outlook express 6 when compacting loses data

hi,
when outlook compacts its email folders,and the computer hangs and restarts emails that was backedup its follders goes missing , i have tried encase , ftk to recover , nothing , those are vital information in those folders , and needs to be recovered any help here would be appreciated. what happens when the folders are compacted ,there must be some sort of temp folder created ,able me to recover ,the only folders recovered is empty folders.

regards

badboy