Osugi Sakae

If you are having trouble unmounting a truecrypt file with
truecrypt -d
(especially if you get a “device busy” message) try umounting it first. You can do this from the command line with:
umount /media/truecrypt1
and then doing the usual:
truecrypt -d
Obviously you may have your truecrypt file mounted somewhere other than /media/truecrypt1, but if you do, you are probably tech-savvy enough to know it. On PCLinuxOS that is the default location. Unmounting first solved the problem for me. YMMV.