Basic question about data recovery

[npish]

I have a 2TB external USB drive that has been corrupted-- i.e. the drive is recognized by windows when attached as it shows in the device manager, but it does not show in "my computer" as an available drive. After doing some research, I found and purchased the program "GetDataBack for NTFS" which fortunately is able to detect the volume and allow for file recovery.

I'm recovering files as I type this-- and praying to the heavens that all works out-- but I'm wondering the following: if this program is able to access the drive and present the file structure for recovery, is there a way that I could simply rebuild the partition (NTFS) / file table so that I wouldn't need to copy all the files to a new drive?

I'm frankly a bit out of my depth here, but it seems like there should be a way for the file table to be repaired so that the drive will mount again.

Any thoughts/suggestions?

[Ash]

After recovery is complete test the drive with all possible test tools to rule out a failing drive (which may not recover your data so well next time it fails)

Make sector-by-sector write test with a utility like badblocks (thats a Linux utility but similar stuff should exist for any OS), the manufacturer's test utility (most/all are included in Hirens Boot CD), and SMART. Some of the manufacturer's tools dont see through USB so you might have to connect the drive internally

If the drive is intact, zero fill it (badblocks can help you here as well), partition and format

[Brad]

If there is anything of importance on the external drive (and apparently there is) in my opinion it is time for a new external drive. They are relatively inexpensive at this point.

Having a corruption on a drive to me is not a good sign. I would not have faith that it would not happen again. You may not be so fortunate in the future to be able to recover your data. There may be other utilities that can get your external drive to mount again though I have not run across them yet.

I have used GTB many times. I have never been able to correct a corrupted drive before. I have at times been able to recover files though which has been an unexpected delight.

Drives fail.

The old saying goes "not if, but when".

Make backups of the backup at least as often as you can afford to lose your data.

My .02c.

Brad

[npish]

Thanks for the responses guys; something I should add is that I know the corruption in this case is my own fault-- I did something extraordinarily stupid while prepping my main drive for a fresh OS install, doing a wipe with DBAN that I put into "auto" mode, and saw to my horror that it began wiping *all* connected drives, not just my main boot drive and I very quickly cancelled the operation-- while it still read 0% in the progress bar for all drives-- but the damage had already been done. Needless to say I have learned my lesson here

Moving forward though, I'm assuming that the basic partition information was damaged by DBAN; however, fortunately, the files do seem to be intact-- *knocks on wood*-- hence my curiosity in seeing if there were simply a way to rebuild the partition structure without having to recover 100s of GBs of data to a separate drive, reformat the existing one and then return the files. At the same time, I realize in trying to repair the partition I could do even more damage and make the files truly unrecoverable.

I do have a secondary backup, but not all the files had been updated from the primary backup. With GDB I was *tremendously* relieved to see that it could retrieve all the directory listings. Thus, via the GDB interface, I'm able to browse files through the disk as if nothing happened...

[npish]

Here's another question though-- once I've recovered all my files, and I want to wipe & reformat the corrupted drive, what software can I use given that I can't actually see the drive in Windows (and thus it doesn't seem to have a drive letter)?

[Ash]

You can try to remove and recreate the partitions from Manage in Windows + format them, if that does not work, use any partition utility with the mot basic partition making/deleting capabilities, nothing extraordinary

I am not familiar with any 3rd party utilities for Windows (but they exist), If you got Linux (live CD is enough) you can use its commandline utilities : badblocks (for scanning for bad blocks as well as wiping entire drive), dd (works for wiping the drive as well), cfdisk/cgdisk (for making partitions with MBR or GPT system respectively), qtparted (same but with GUI), and mkfs.ntfs (for formatting, but when you get to this stage the partitoins will show up in Windows again and youll be able to format them from there)

[RealBlackStuff]

You cannot reconstruct the partition table in any easy way, that is what DBAN had started wiping.
But anything AFTER where DBAN stopped wiping, will still be perfectly OK.
DBAN did not corrupt the HD at all, it just wiped a small part including MBR, (part or all of) partition table and possibly a small part of the files.
If you want the rest of those files, just continue to recover them all.
After you finish recovery, click on Start/Run (or Start/Search in W7), type in diskmgmt.msc and hit enter.
There you can repartition/reformat the HD the way it was.

If you really are a file buff, there is software out there (testdisk) that could reconstruct your partition table from the files that are still on the HD.
It's part of the Gparted partition manager. http://gparted.sourceforge.net/h2-fix-msdos-pt.php
I'd be very weary of using it though!

[npish]

Thanks RealBlackStuff, that is extremely helpful-- and reassuring. Given that reconstructing the partition table seems like no simple task, I'll go forward with recovery via GDB.

Another question though-- I opened up the disk management console, and I'm seeing the disk listed in black with the whole partition marked "unallocated." Once recovery of the files is complete, how should I proceed? If I right click on the partition, I see an option for "New simple volume"-- would this be how I'd commence formatting the drive?

[RealBlackStuff]

What OS are you using?
Under XP, rightclick in the leftmost block, where it says 'Disk 1' or 'Disk 2' (assuming one of them is the HD in question).
It may offer the option "Initialize". If so, do it.
If not, rightclick on the 'unallocated' or other partition(s) and Delete if possible, then Create new, and Format as per your liking.
Don't have W7 handy at the moment.

[npish]

Just to provide an update here-- fortunately, I was able to recover all data from the corrupted drives with the help of GDB-NTFS (needless to say, I have learned a hard lesson about playing "fast and loose" with something like DBAN, ha.) I'm on Windows 7 and using the disk management utility, as suggested, (once all the files had been recovered), I was able to create a new volume and format from there.

Thanks for all the helpful feedback.