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I installed yesterday ubuntu 11.10 on my 80GB hard drive and i can't change files permissions on my second hard drive.

How to fix this?

ps: i have dual-boot with win7


/dev/sda5 on / type ext4 (rw,errors=remount-ro,commit=0)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
fusectl on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev)
gvfs-fuse-daemon on /root/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev)
dev/sdb1 on /media/600CA8AD0CA88020 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096,default_permissions)
share|improve this question
Can you provide some more information? When you say you installed Ubuntu on your 80GB hard drive, is this the first hard drive or are you referring to the second hard drive again? What file system is in use on the second hard drive? The line of output from mount corresponding to the second hard drive would be useful here. – James Henstridge Dec 8 '11 at 7:50
in my first hard drive i have installed ubuntu and win7, on my second i don't have any system, i don't know how to use the command mount. – derekk_m Dec 8 '11 at 9:27
...and why change file permissions on the second HDD? What's wrong with them? What file system is there? – mikewhatever Dec 8 '11 at 9:50
may be you mean change owner? chown is what you need then! – Stefano Mtangoo Dec 8 '11 at 10:01
@derekk_m: open up the terminal and run the command mount. Partitions from your second hard drive will probably turn up as /dev/sdb1, sdb2, etc. If you could provide those lines of output, it should help answer the question. – James Henstridge Dec 8 '11 at 10:23

Based on the mount output, it looks like your second hard drive is formatted with the NTFS file system. This isn't a bad choice if you want to be able to access the files from both Ubuntu and Windows, but has slightly different semantics to native file systems.

The NTFS driver does have support for mapping Windows user IDs to equivalent UNIX user IDs though, which might help. There is a tool called ntfs-3g.usermap that can help you build up the user mapping:

  1. First unmount the NTFS partition by running sudo umount /dev/sdb1 from a terminal.

  2. Build up the user map by running sudo ntfs-3g.usermap /dev/sdb1 in the terminal. Provide the Ubuntu user account names for each Windows account you want to map. The program will create a file called UserMap in the current directory.

  3. Remount the file system and copy the UserMap file to the special .NTFS-3G directory:

    sudo mount -t ntfs-3g /dev/sdb1 /mnt

    sudo mkdir /mnt/.NTFS-3G

    sudo mv UserMap /mnt/.NTFS-3g/

  4. You may need to unmount and remount the file system again to make this user mapping take effect.

Once this user mapping file is in place, your Ubuntu user account should have access to any files or folders owned by your Windows account, and any files you create in Ubuntu should look like they were created by your Windows account when you boot Windows.

share|improve this answer
Is there a way to reset this "mount" to default? – user37271 Dec 9 '11 at 14:27
Default in what way? The NTFS file system supports permissions, so that is what is the default behaviour. The file system driver does support squashing all files down to the same user/group ownership, but that is not a default option. – James Henstridge Dec 10 '11 at 10:40

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