Drives have disappeared in My computer

I have a windows 2000 workstation that has lost all drives in my computer – Its like they are invisible. Also in windows explorer all folders/files on the right side of the screen don’t show up. If I click on any folder listed on the left side, the contents that usually show on the right side are invisible. This PC caught some kind on trojan and virus and i noticed this after the infection. Any suggestions to fix this?? I already ran the virus scan, trojan hunter and spybot which removed the infected files and trojans.