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First here's my Partition Table reported by fdisk.

Disk /dev/sda: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 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: 0x4633d875

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          64      512000    7  HPFS/NTFS/exFAT
/dev/sda2              64         128      512000   83  Linux
/dev/sda3   *         128         321     1552384   83  Linux
/dev/sda4             321      243201  1950934624+   5  Extended
/dev/sda5            6151       18309    97667167+  83  Linux
/dev/sda6           41285       99436   467105940   83  Linux
/dev/sda7          104066      167304   507967267+   7  HPFS/NTFS/exFAT
/dev/sda8          188269      243201   441249322+  83  Linux

Here's my setup:

  1. I installed Ubuntu 12.04 / (root) in one partition of around 100Gb.
  2. /home is another partition around 500GB
  3. /boot in /dev/sda2 500MB
  4. 800GB another partition hope its in /dev/sda8
  5. /dev/sda7 of 500GB contains Windows 7
  6. /dev/sda1 has windows boot files

Q: How my PT got corrupted?
A: I wanted to try win 8 so I shrinked /dev/sda7 to 400GB/100GB using windows 7. After restart i could not boot my linux, windows 7 booted fine. So i panicked and extended the /dev/sda7 partition back to 500GB. And rebooted ahhh. Now its completely not booting. Then I created ubuntu live cd in usb and used testdisk and fdisk to recover my partition table (no luck so far).

Partitions /dev/sda1 and /dev/sda2 (primary partitions) are mountable and working fine. But I have lots of important data in /home and /dev/sda7, /dev/sda8 partitions.

It seems that the extended partitions start/end sectors are not valid. Please help me to resolve this.

PS: I ran testdisk 3 times, each time it takes >4 hours to finish.

Advanced thanks for your kind help :)

share|improve this question
What's the error message you get when trying to mount one of the corrupt partitions? Also check messages in dmesg. – siebz0r Nov 22 '12 at 15:37

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