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I do not what happened, but i can not anymore automount my hard drive. It contains a vital data for me and have no whish losing it. Any help is very much appreciated

i was trying to copy somes files from my Ubuntu machine to my windows. I copied my files correctly, and unmounted my partitions one by one. Then plugged the hard drive to my windows machine. Which showed a weird error looking like 'error when writing some/system/file/ending/by/pointers'. I suspect windows did something nasty to partition table which make mount/umount operations to be mabe.

as for the symptoms:

  1. Ubuntu's and windows' automounts cannot mount the HDD partitions
  2. My hard drive is seen as /dev/sdb*

    XYZ@samtop:~$ ls /dev/sdb*
    /dev/sdb  /dev/sdb1  /dev/sdb2  /dev/sdb3
  3. manual mount loops forever:

    XYZ@samtop:~$ sudo mount /dev/sdb1 /media/exdrive1/

Could anyone, please, give me somes hints. Much appreciate it

share|improve this question
How is the drive formatted? – Mitch May 9 '13 at 11:19
1. In Windows, did you do the "safely remove hardware" before unplugging the drive? 2. What is the output of dmesg | tail after an unsuccessful mount? – ignis May 9 '13 at 14:13
mitch, ignis. Thank you for your support. The drive is NTFS formated. In windows, i made the mistake of plugging the HDD into an an USB port with low power supply. It hadn't been correctly mounted, so i hadn't the chance of 'safely' removing it – mbelaoucha May 9 '13 at 19:20

In windows, i made the mistake of plugging the HDD into an USB port with low power supply. It hadn't been correctly mounted, so i hadn't the chance of 'safely' removing it. As soon as I plugged the HDD i got a notification message from Windows saying that it failed in writing a system file which got 'pointers' at it end.

The drive was well formatted, in NTFS

XYZ@samtop:~$ fdisk -l
Disk /dev/sdb: 500.1 GB, 500107862016 bytes
240 têtes, 63 secteurs/piste, 64601 cylindres, total 976773168 secteurs
Unités = secteurs de 1 * 512 = 512 octets
Taille de secteur (logique / physique) : 512 octets / 512 octets
taille d'E/S (minimale / optimale) : 512 octets / 512 octets
Identifiant de disque : 0xc701c701

Périphérique Amorce  Début        Fin      Blocs     Id  Système
/dev/sdb1   *          63   102398309    51199123+   7  HPFS/NTFS/exFAT
/dev/sdb2       102398310   532474424   215038057+   7  HPFS/NTFS/exFAT
/dev/sdb3       532474425   976768064   222146820    7  HPFS/NTFS/exFAT

here is the output of 'dmesg'

XYZ@samtop:~$ dmesg | tail
[ 1192.198597] sd 8:0:0:0: [sdb] Unhandled sense code
[ 1192.198608] sd 8:0:0:0: [sdb]  
[ 1192.198612] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 1192.198616] sd 8:0:0:0: [sdb]  
[ 1192.198619] Sense Key : Medium Error [current] 
[ 1192.198626] sd 8:0:0:0: [sdb]  
[ 1192.198631] Add. Sense: Unrecovered read error
[ 1192.198636] sd 8:0:0:0: [sdb] CDB: 
[ 1192.198639] Read(10): 28 00 00 00 00 00 00 00 08 00
[ 1192.198662] end_request: critical target error, dev sdb, sector 0

well, i guess something is going really wrong! but do not know what this means. Trying to google it in the mean while.

share|improve this answer
That means you've hit a bad sector. Which is not a good sign.... And on the first sector... – derobert May 9 '13 at 20:55
I'd try to get data out of it with smartctl. Hopefully it supports the USB bridge the drive uses. – derobert May 9 '13 at 21:03
Hi derobert, do you mean that: 1) there is no way to mount correctly my filesystems, and 2) there is no hope using my hard drive again? ... well this is most infortunate stuff! – mbelaoucha May 10 '13 at 0:32
Well, it means that sector 0 appears damaged. That's not good, but is recoverable if its just a bad sector. smartctl will hopefully let you know if its just a bad sector, or if you've got bigger problems. – derobert May 10 '13 at 14:53
well, at the end it appears that my problem was a hardware issue. I bypassed the USB bridge, and plugged the sata port into a laptop. Instead of errors on 'sector 0' only, i've ended by having an error by sector in a partition (when trying do dd). – mbelaoucha May 15 '13 at 22:57

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