Comment 25 for bug 711799

I now tried in single user mode and there I could run the check. It even said it was clean? (Looking at what tune2fs said, that is - for me - surprising).

I did run lsof on the partition, but it did not return anything.
It might have been an unclean shutdown of gparted, leaving either parted or ntfsresize as zombies on /dev/sdb. That happened today, but was visible in lsof. But yesterday I did not run fdisk -l, which is quite useful to see more information on what the kernel knows.

I also run the check with the -c option, but no error was mentioned. Everything turned out the be clean.

I then removed /dev/sdb1 from /etc/fstab and continued to boot normal. Then I could change the size of the partition (that was my initial goal). Afterwards I added it back and all seems to run smooth now.

So if anyone runs into the same problem, here is what to check:
0. umount /dev/sdb1; mount |grep sdb1
1. lsof /dev/sdb1
2. fdisk -l
3. cat /proc/mounts

4. remove partition from /etc/fstab and boot into single user mode (press e on grup and add "single" at the end of the kernel line, then press ctrl-x to boot). There check again.

5. If all fails, come back here ask again :)