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I have an external drive that has only my user with read-write (all other groups as read-only).
So when I mount it on another computer, I can't write to it. Yet, even though I am the owner, I can't change permissions to read-write for all, even if I
Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00012a16 Device Boot Start End Blocks Id System /dev/sdb1 2 1953525167 976762583 7 HPFS/NTFS/exFAT