A while ago I had two hard drives on a computer, one hard drive I used for backup, and the other one had the OS. When I was ready to upgrade the computer to WinXP, I unplugged the backup hard drive, upgraded, then plugged the backup hard drive back in. When I went to access it, it said it was not accessible and it had a RAW file system. Maybe it was just the way the OS was communicating with the hard drive, and since it was from a previous OS version, the OS didn't know what the heck the data/organization was on the second hard drive, so it couldn't address it, (just a theory).....well, what I did was run a data recovery software, and the files were successfully retrieved quickly and in good condition. Apparently, the data was still in tact, just the OS had no idea what it was, how to interact wit hit (again, just a theory). It took me a while to find a good recovery program, though, but the one I use, I continue to use, and it provides various options for how you want to recover the data (i.e: recover data when the hard drive contains no partition information, recover when in RAW format, etc)....the name of the program i use is Easy Recovery Pro
If the format did somehow someway format the external hard drive, then DONT format it again, you may make it more difficult to recover the data. Simply find a good data recovery software and run that. I'd start in Download.com and run a query for "data recovery"
Interesting article what is possible and what isn't possible with data recovery:
www.runtime.org/recoverability.htm
You may have needed a (DDO) dynamic drive overlay for the HDD to cooperate with the os you usually have to put a DDO on larger drives to format then install a base windows and not format using windows but using the DDO b4 hand instead
