I have a external HD that I can't seem to open. When I try to open it with gparted it says unrecognized disk. When I run gparted from the terminal this is what it says.
Might be that the disk label has not been initialized yet. Is this a new disk, or has it been used before? If it's already been used: under which OS and version?
I also get this message when I try to mount the HD. I tried with and without the force option.
~ $ sudo mount -t ntfs-3g /dev/sdb /media/hd-ntfs -o force
NTFS signature is missing.
Failed to mount '/dev/sdb': Invalid argument
The device '/dev/sdb' doesn't seem to have a valid NTFS.
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?
~ $ sudo mount -t ntfs-3g /dev/sdb /media/hd-ntfs
NTFS signature is missing.
Failed to mount '/dev/sdb': Invalid argument
The device '/dev/sdb' doesn't seem to have a valid NTFS.
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?
---------- Post updated at 04:57 AM ---------- Previous update was at 04:55 AM ----------
It has a NTFS partition. I use it in both windows xp and Linux Mint which is very similar to Ubuntu.
Clearly the boot sector's been stomped on somehow at the very least.
Try sudo dd if=/dev/sdb count=$((2*16384)) | hexdump -C | less which should show a binary dump of the first sixteen megs of the drive. Hunt for NTFS in that listing in less by typing "/NTFS" and hitting enter. If it finds it that means the partition might still exist and might still be accessible if you can create a partition on the disk matching it's exact placement.
I saw it a few times. How would I pipe that in a log file? Less keeps on getting stuck on me when I try to search. This is the command I used and it just made a empty log file.
Much like I said; create a boot sector that matches the place where you found the partition. Without knowing where you found NTFS though, that may be difficult. I'm reluctant to give too general instructions lest it be my fault your drive gets messed up.
Here's a dump I managed to get from the very start of an NTFS partition:
See the 0xAA55 at offset 0x7FFD. This is the signature for the end of the NTFS boot sector. $BOOT in NTFS MFT terminology. This is MFT entry 7. It is the only NTFS metadata file that has a static location.
Per NTFS design docs, a backup copy of the boot sector always exists either at the middle of the volume or at last. To date, the backup copy has been placed in the last sector. Compare these two sectors to see if there is a difference.
Frankly, I don't think you will find a difference. Something else is going on. Did you "unmount" this disk cleanly the last time you used it?
I wasn't given the ability to do that. I was watching some videos in XP and all of a sudden I couldn't access my data any more. I don't understand what happened. I thought watching some videos is a very simple thing.
If my memory is correct you have to have a drive letter for chkntfs to work correctly. Is that correct? In windows It has no drive letter. I am also not able to assign it a drive letter with disk management. Is there a way to ignore this problem?
Well, my directions would've been on how to get that partition table back. That it has is both very good and very bad news; something's seriously wrong with either the drive or the USB cage for a sector to just vanish and return like that! Also good that you posted it here. Armed with that you have enough information to recreate it from scratch if it vanishes again.
If windows doesn't see the partition table, first off I would rewrite the same partition table back to it, just 'w' from fdisk /dev/sdb. If there's anything odd in it preventing windows from seeing the partitions, that may clear it.