I was planning to move some files around and archive my system backups to 1 of my USB Eternal Drives.
I have 2 USB External HDDs and had them both plugged in and working fine, before I started doing anything, I accidently unplugged the power on one of the USB drives and a Delayed-Write Error message came up and told me the folder it encountered the problem on. (Now, I haven't done any activity on this PC in at least 2 days, so I don't know why I would get a delayed write now).
I plugged the power back in for the drive, but couldn't access it.
So I turned the PC off and rebooted.
When it came back up, neither drive was appearing in My Computer.
I tried un-plugging and plugging them back into the usb port. I heard a windows clunk-clunk sound (like a new usb device was added) but I still can't find either of the drives in My Computer.

suggestions?