I got into a weird situation. I got a 1Tb portable HD filled with some contents. It was used in Windows and as always packed with virus. I tried deleting some folders as root. But the following error returned
rm -R RECYCLER/
rm: cannot remove `RECYCLER/S-1-5-21-1659004503-1644491937-725345543-1003/Dc39.pptx': Operation not permitted
rm: cannot remove `RECYCLER/S-1-5-21-1659004503-1644491937-725345543-1003/Dc58.docx': Operation not permitted
rm: cannot remove `RECYCLER/S-1-5-21-1659004503-1644491937-725345543-1003/Dc17.JPG': Operation not permitted
ls -l
returned
Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xf898cc8b
Device Boot Start End Blocks Id System
/dev/sdc1 1 121602 976760536 7 HPFS/NTFS
ls -l RECYCLER/
total 12
drwxrwxrwx 1 user user 12288 Dec 11 21:13 S-1-5-21-1659004503-1644491937-725345543-1003
mount
provides this information.