I had the same problem .. check your server /tmp folder if it is 100% delete it and the categories will reaper
root@server [/]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/md1 61G 38G 21G 65% /
tmpfs 12G 0 12G 0% /dev/shm
/dev/md0 1008M 69M 888M 8% /boot
/usr/tmpDSK 546M 518M 0 100% /tmp
root@server [/]# rm -r -f /tmp
