Can’t access partition on external hard drive

[BigBluffer]

Before I had to reformat my internal hard drive, I had the following drives/partitions:

Internal hard drive: C: and D: partitions
Internal DVD/CD-RW drive: E:
Internal media card reader: F: G: H: I: drives
External 300 GB hard drive: J: and K: partitions

I used the J: drive primarily for key backups from C: and D:.
I used the K: drive for most of my music and pictures files.

Sometimes, when booting up the computer, or turning on the external hard drive, the K: drive would not be recognized, and I’d have to turn the drive off, then turn it on again. This is key to the cause of my problem.

I had to reformat my internal hard drive. When I reformatted it, I only created a C: partition. Stupidly, I forgot that Windows would reassign the drive letters to my other drives/partitions. My external hard drive would be assigned I: and J: partitions.

The first time I booted up the computer after the reformatting, I noticed that the J: drive wasn’t being recognized. My thoughts were that the external hard drive wasn’t being recognized for some reason. Remember, I was expecting to see both J: and K: drives in Windows Explorer. So, I turn off the external hard drive and a few seconds later turn it back on! WRONG MOVE!

My son, who is a bit more technically oriented than I am, told me it turns out that at the moment I turned off the external hard drive, the J: partition was being read and loaded (forgive me if that’s not the right technical term), and by turning it off at that moment, I corrupted the FAT for that partition. With a corrupted FAT, the data on the partition cannot be accessed. In fact when we look at a picture of the drive, we see the I: partition, but the rest of the drive is “unassigned” (or something along those lines). I am told that most, if not all, of the data on the J: partition should still be there intact, if I can only get to it.

The I: partition can be used normally.

I'm running Windows XP Pro.

I realize I screwed up big time. Any ideas on how I can recover the data on my J: drive? Any help would be much appreciated. Thanks in advance.

[Spota]

Shouldn't matter. Can you plug the external drive (I'm assuming USB?) into another PC?

[BigBluffer]

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Shouldn't matter. Can you plug the external drive (I'm assuming USB?) into another PC?

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Yes, it's a USB drive.

Just tried your suggestion with no luck. Any other ideas? Thanks.

[buckslayer80]

You shouldn't have a problem powering down a drive while its being read. It's not recommended, but look at what you can do to an internal drive. You can turn that thing off whenever you want as long as it's not formatting itself. Someone correct me if I'm wrong, but unless external USB drives are any different, then he shouldn't have any problems. Did you reassign the unallocated disk space with another drive letter yet?

[kerowo]

Try going into Control Panel > Administrative Tools > Computer Management > and defragging the disk, that might cause Windows to scan the disk and fix the corrupted FAT. Or you can type CMD or COMMAND in the Run box of the start menu and run CHKDSK for the good partition on the external drive, CHKDSK I:
you can run it this way and it will just scan, add an /F for it to fix problems it finds.

[BigBluffer]

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Did you reassign the unallocated disk space with another drive letter yet?

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No. I didn't want to do that on the chance it would overwrite any data on that partition. I figure if I just leave that partition alone until I recover the data on it, I won't accidentally lose the data permanently.

[BigBluffer]

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Try going into Control Panel > Administrative Tools > Computer Management > and defragging the disk, that might cause Windows to scan the disk and fix the corrupted FAT.

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The Disk Defragmenter window identifies the I: partition. It's a FAT32 partition with a 39.05 GB capacity and 18.97 GB used. I clicked on the Analyze button and when it finished it told me I do not need to defragment this volume. It did not see the larger partition. Should I defragment the I: partition anyhow?

[ QUOTE ]
Or you can type CMD or COMMAND in the Run box of the start menu and run CHKDSK for the good partition on the external drive, CHKDSK I: you can run it this way and it will just scan, add an /F for it to fix problems it finds.

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I'm doing this next. Thanks.

[CORed]

What you are describing looks to me more like a corrupted partition table than a corrupted FAT, although I can't say for sure. Something you might try would be to create a new FAT partition from the unassigned space in the disk manager, but DO NOT format the partition. The danger here is that if the partition doesn't exactly match the starting position of the old partition, you still won't be able to access your data, and could possibly overwrite some of it. If the problem is indeed a corrupt FAT, this probably won't help.

If the data on the drive is important enough to you to spend big bucks, you could send it to a data recovery company. This can get very expensive, although since you drive is apparently not physically damaged, it's might not be as expensive as a drive that has completely failed. Although the data is still there, without a working file system, it's just random bytes, and recovering it to a usable form may be a pretty difficult undertaking, depending on how badly fouled up the FAT, root directory, etc. are.

As another poster wrote, powering the drive off while reading shouldn't normally cause a problem, but it appears that in your case it did. Powering off a drive while it's writing is more likely to cause problems.

FAT is a very fragile file system. If your data is important, you would probably be better off using NTFS. Most external drives come preformatted with FAT32, but they can be reformatted to NTFS. Thee is also a utility to convert FAT to NTFS, but it is a good idea to back up your data before using it.

[BiPolar_Nut]

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You can turn that thing off whenever you want as long as it's not formatting itself. Someone correct me if I'm wrong, but unless external USB drives are any different, then he shouldn't have any problems.

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Powering off during reads = no problems, and you are correct in USB drives being no different than internal drives. The only thing different is the drive controler, but the drive itself is still IDE or SATA. Powering off a drive during a write == bad news, for an internal or external, PATA or SATA IDE, SCSI, fiber channel, floppy, CDR, DVDR, etc.

Since disk management is sinmply showing unassigned rather than unpartitioned space, you're prolly in good shape and simply need to assign a drive letter. It'd be best to reboot immediately after a drive letter change, and make sure nothing is accessing the drive (like a windows explorer window showing any folders on it). You could even change the drive letters back to what you're used to (J: and K, so you don't need to change stuff like playlist paths.

[BigBluffer]

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Or you can type CMD or COMMAND in the Run box of the start menu and run CHKDSK for the good partition on the external drive, CHKDSK I: you can run it this way and it will just scan, add an /F for it to fix problems it finds.

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I ran chkdsk I: /F and got this report:

The type of the file system is FAT32.
Volume Serial Number is xxxx-xxxx
Windows is verifying files and folders...
File and folder verification is complete.
Windows has checked the file system and found no problems.
40,947,648 KB total disk space.
5,696 KB in 97 hidden files.
76,128 KB in 2,373 folders
20,968,768 KB in 34,264 files.
19,896,992 KB are available.

32,768 bytes in each allocation unit.
1,279,614 total allocation units on disk.
621,781 allocation units available on disk.

Still no J: drive being identified.