Today I tried to fix a broken NTFs hard disk. I was able to read parts of the disk by
dd if=/dev/sdc1 of=rescue.dd.img conv=noerror,sync
When the disk started to give too many errors, I skipped some gigabytes and continued to read from further away (note by default dd reads 512bytes at a time)
dd if=/dev/sdc of=rescue.dd.img skip=10000000 seek=10000000 conv=noerror,sync
To make the rescue.dd.img equal size to the original (added 1.3TB), I ran truncate, which was instant unlike dd
truncate -s +1329705307136 rescue.dd.image
Then I ran
ntfsfix -f rescue.dd.img
But then I got error
> mount rescue.dd.img /media/windows
Failed to read last sector (2930272255): Invalid argument
HINTS: Either the volume is a RAID/LVM but it wasn't set up yet,
or it was not setup correctly (e.g. by not using mdadm --build ...).
or a wrong device is tried to be mounted,
or the partition table is corrupt (partition is smaller than NTFS),
or the NTFS boot sector is corrupt (NTFS size is not valid).
Failed to mount '/dev/loop0': Invalid argument
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?
Thanks to this article I managed to mount the disk
sudo ntfs-3g -o force,rw rescue.dd.img /media/windows
Success!