I'm starting to run out of space on my MBP, so its time to compact. However, When I run he compaction (31G HD 13G used) it prepares fine. once it goes to compact I get this error: Process of compacting of the virtual hard disk /Users/<ME>/Documents/Parallels/XP - parallels/winxp.hdd was abnormally terminated due to the unrecoverable error. If the problem is something I have to reinstall to fix that I'm pissed. Thanks.
solved Turns out you need a bunch of free space on the HD to compact... So i copied it to an external drive, used the image tool to split it, and then compacted it. worked like a charm.