Can't access partition on external hard drive

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 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 “unallocated”. 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.

 

There are other freeware recovery tools, but try
http://www.majorgeeks.com/TestDisk_d4803.html