Compaction just removes wasted space in the files and needs to be done on a
routine basis to help prevent bloat and also maintain performance.

You don't want to undo it. See point 2 here for issues related to
compaction and also for information on the latest patch that addresses this
issue: www.oehelp.com/OETips.aspx#2

If you lost messages, then see point 4 on that page. You may need to get
DBXpress to try and recover the messages.

steve

"Stan" wrote in message
news:QzyEg.404817$iF6.48679@pd7tw2no...
Everytime I closed Outlook Express, I would get a pop up window asking me
whether I wanted to compact my files. Space was never an issue so I always
said no. Tonight I accidently clicked yes and all my folders in outlook
express go compacted.
Can I reverse this process?