Windows 7 - Hard Drive Issue

I turn on my computer and it does it's usual BIOS check, CD/DVD drives detected, both hard drives detected, ect.
But when I boot into Windows, either XP or 7, my secondary hard drive shows up on Rainmeter as "0.0 B/0.0 B Used"
Every time I try to go into the drive it says "D:/ is not accessible. The file or directory is corrupted and unreadable."

I have 120GB of data on that drive I want to recover, a lot of my time and work are on it. Please tell me there is a way to get all the information, is not some of my most important information of the drive.

Try this:
Redirecting...

Check the hard drive with the manufacturer's diagnostic tools.
Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp.
HD Diagnostic

And, as far as recovering your files, I would try:

Copy & Paste - in Windows Recovery Console


and if that method fails:
Use Ubuntu Live CD to Backup Files from Your Dead Windows Computer - How-To Geek

James