I had a workstation running XP. Filesystem was NTFS, single partition over the entire drive. After an attempted XP repair install, suddenly the NTFS filesystem is just gone and the drive is showing up with a single 10Mb FAT32 partition with virtually nothing on it, except a directory with a smiley-face character (e.g. not good).
I've run all the tools I could find on the UBCD and nothing is able to detect the missing NTFS partition. I've run some low-level tools on the drive and it checks out ok. I'm not ruling out hardware, but that's not really my question.
What are my options here for recovery?
Update: I was never able to recover the partition, but I did recover a lot of data using PhotoRec (from the same guys who do TestDisk, recommended in the answers below). The name is misleading as it doesn't only recover "photos", as I had originally thought. It does some 180 file formats.
The one, the only. TestDisk. Here's a rundown of the entire process.
Gpart (not gparted) can recover missing partitions, by guessing where they are. It's a Linux tool, so it's on some of the recovery liveCDs.
I very recently had a similar issue, but i have been saved by Partition Find and Mount.
There's a free version, although it has a speed limit (512Kb/sec). But that didn't keep me from copying 60 gig off a lost partition (it took more than a day though).
The first thing you need to do is to make an image of the drive, so you do not ruin it more while attempting to recover it. Boot any live linux CD (Knoppix, Ubuntu, whatever), and use dd to dump the disk data on another storage.
dd if=/dev/sda of=/mnt/myexternaldrive/olddrive.img
where /dev/sda is the old (broken) drive, and /mnt/myexternaldrive is the mount point where you mount your external (or secondary) drive.
Then, you can use fdisk (or parted, or gparted), and just create an NTFS partition, which occupies the whole drive, and try to mount it.
If this mounts, but there are no files, you can try running some file recovery software line ntfsundelete.
Check out easy recovery professional
http://www.ontrackdatarecovery.com/file-recovery-software/
I believe you can scan to see what it will pick up before you need to buy to recover.
Sounds like a virus, so be careful what you recover it to.
one way if have any livecd like ubuntu or kubuntu u can boot a system dont install once desktop screen come u can mount u r hdd and try copy to other hdd external or over the network.
second way of doing is u need have recovert tool like setter software which recover software.
Ubuntu includes some tools that can find files on the drive directly.
I've used photorec on deleted image files (not sure how it does on bad/missing partitions.)
Here's an Ubuntu howto on Data Recovery.
Make sure you output the recovered data to a different drive to avoid killing what you are trying to recover.
Probably your best choice would be to try TestDisk.
Depending on your comfort with linux/bsd you can try the combination of fdisk or gpart. Also, the FreeBSD setup disk has some interesting tools you might try.
To play with this, go into the installer and select 'upgrade system.' This will show you what partitions it knows about on the disk and allow you to configure a new layout. As the instruction say, this is not going to write the layout to disk, but needs to be done to proceed with the upgrade process. After that, you'll be given a terminal on vty4. Switch to this term and see if you can see your files. This could get you back to a bootable state, but will most certainly help you see and interact with the partition.
Best of luck.