I have 2 hard drives with a total of 12 partitions. (System is Windows XP, SP2) When I open Windows Explorer, it shows drives C through M, which are various logical drives. Next comes drive N, which is my DVD burner. Following that is drive P, which is labeled removable disk. I have no removable disks on my computer. If I click on this drive, I get the message "Please insert a disk into drive P:". (Following drive P is drive Q, which is another of my logical drives.) My partitioning arrangement is as follows: drives C, E, F, G, H, I, J, and Q are on hard drive #1. Drives D, K, and L are on hard drive #2. Does anyone have any idea what is causing this phantom drive P to appear in Windows Explorer?

No CD drive, or does the DVD burner also read CD's?
If so, Windows may be seeing this function as a separate drive.
When you put a CD in drive N, check My Computer and see if it shows it in drive N or drive P.

When I put a CD in DVD burner, My Computer shows it as drive N. It lists drive P as "Removable Disc".

Have you tried deleting the drive in device manager?
If so, does Windows "find" it when you reboot?
Sometimes, task manager will continue to report hardware that was once installed on the computer, but has been removed.
Deleting it there will usually get rid of such phantom hardware.

It doesn't show up in Device Manager. I do have a "VIA SATA RAID Controller" in Device Manager, whatever that is.

Does the controller show up under system devices or disk drives? If Windows is seeing it as a drive, this could be your drive P.
What level of RAID are you running on your hard drives?
The RAID controller handles the writing of data to your hard drives.
RAID provides either data redundancy or speed. It is widely used on servers, so that when a drive fails you simply pull it out, plug in another and the controller writes the data on to the new drive.

As far as I know, I'm not using RAID on any of my hard drives. Under Disc Drives, besides the 2 hard drives is listed "HP psc 2410xi USB Device". This is my printer. Could this be drive P?

If it is listed there , then Windows is seeing it as a drive.
Strange. That would be the drive P that you are seeing.

OK. Thanks for all the help.

   I am going through the old posts and I saw this one and others that I could have answered.  I am sorry that I am so late in posting.  I think that I was in Russia when these were posted.  That may be why.
   I have four drives that are marked Removable Disk.  They are I-L.  My computer, which I purchased brand new, came with them already on it.  I think that they are various memory card readers on the front of my computer.  I never use them.
   There are also four USB Reader devices under Disk drives in the Device Manager.  They are as follows:
Generic USB CF Reader USB Device
Generic USB MS Reader USB Device
Generic USB SD Reader USB Device
Generic USB SM Reader USB Device
   The letters on each of these correspond to the letters labeling each of the memory card slots.