Have you tried checking the filesystem for errors? Install the dosfstools package and run /sbin/fsck.vfat /dev/hda6 as root.
Don't do this with the filesystem mounted. -- After using fat parittion it becames read-only https://launchpad.net/bugs/58451 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
