I have a dell 4400 desktop with windows xp. I upgraded the cd drive to dvd drive. It has been working ok until now. My computer doesn't reconize it. I had to install Nero for the dvd drive because it wouldn't work with media player. What can I do? I wanted to try to correct it before putting it in the shop. I tried to do a system restore and my computer will not let me go back. I check the system restore setting and it's on but it doesn't want to let me go back in time. I can't figure out what on earth is causing that. I may have to have windows xp wiped out and reloaded. Can anyone help? Oh by the way I put in a cd drive this morning to see if the dvd player was bad and the computer will not operate it either. I gave me a message that the "IN CD helper in not correctly installed". Is this my problem? Where can I download it?