My Book not recognized after reinstalling windows xp

I was using My Book every day and all was fine.  I had to reinstall my windows XP Pro - same version as before.  After the install I see My Book E: on my directory but it appears empty of files.  When I ran a virus scan on it I could see all my files scrolling by so I assume they are still there.  Do I need to reinstall My Book?  I’m not sure I have any software for it. Can anyone help me with this? 

What is the model number of your drive, and did you used a backup software? If so, please provide us with the name.