Changes after installing Service Pack 2
The backgound compaction feature is removed from OE after you install WindowsXP Service Pack 2. Instead of compacting in the background, which was often the source of problems, OE now waits until you open and close the program 100 times. After that 100th time OE begins to compact. Do NOT stop this process! Do NOT turn off your
computer or put it into Standby (Sleep) mode! Do NOT use your
computer until the process if complete! Doing any of these things can cause the compaction process to fail and result in lost messages
Clean Up Now Options
Compact
This will remove any wasted space and will free up some disk space.
If this somehow does not work you can do the registry hack on bottom of article. Just make sure you back up your registry first.
Terry