Thinkpad 600e not recognizing HD

hbg

I hjave a Thinkpad 600e which was working quite well with a 10gb HD. I put in a 20gb, and it would not work, I had problems still when I pu th e10 gb in. I did manage to load win 2000 on the 20 gb. however, when i took it out, and put it in the caddy, I have not had success with either drive.

Any ideas