Remove CD rom drive in WinXP

Hi there MGs

My explorer program shows that I have a CD rom drive assigned to the letter D:

The problem is, I don't even have a CD drive. I have a DVD drive which correctly shows up as drive E:

I checked out system admin tools and it doesn't appear there, so I can't remove it from there. So I guess my question is how can I remove the appearance of a physical drive from explorer when it doesn't exist in the first place?

Also while trying to solve the problem I assigned one of my hard disks (there are four) the letter K: just to get it out of the way for a while. However, now that I would like to return it to its rightful letter the system does not give me a choice of any letter before G: (it originally was letter D

So summary my explorer shows:

A: Floppy drive (havent got one)
C: Main boot disk
D: CD rom (computers imagination)
E: DVD RW drive
F: Hard disk external
H: Hard disk external
K: Hard disk internal

I would like it to show:

A: Floppy drive (havent got one - but I may connect one up)
C: Main boot disk
D: Hard disk internal
E: DVD RW drive
F: Hard disk external
G: Hard disk external

Any ideas?

Cheers

Charco