D:\ drive not showing up

Occasionally, my drive D (a cd drive) does not show up in My Computer, and will not load discs. this is very troublesome, as the computer needs restarting and other family members who use this computer get angry about being logged off after i restart. is there any way that i can find drive D without having to restart?

 

the drive is always present at startup, however something occurs while i am on the computer which makes it disappear. the drive is always present at startup, however, some time while the computer is running, the disc drive disappears. the cables are all inserted properly (i checked) and it runs fine, then all of a sudden, BOOM!!! it stops working and disappears.

 

i have, but ad-aware and spybot dont work anymore... are there any other good programs i could use?

 

JCDenton_4, what operating system are you using?

If it's XP, then follow THESE steps. (Don't worry about deleting the files, Windows will replace them)