Wadd, based on what you said, I think it's very possible that the hard drive I first added was the system drive in another machine, and I added it to this PC before repartitioning and installing windows. What youre saying makes sense, however, why would adding this 3rd, non-system non-boot disk mess up what was previously working? This drive has always been used as an external and has never had any system information or OS loaded on it. I'm afraid you may be right about just starting over... but I'm going to sit here with my fingers crossed for a while... and thanks to everyone for their suggestions so far.

I think your boot.ini might need some fixing try this:

1. Insert and boot from your Windows XP CD.
2. When you receive the "Press any key to boot from CD" message, press a key to start your computer from the Windows XP CD-ROM.
3. When you receive the "Welcome to Setup" message, press R to start the Recovery Console.
4. Press the number that corresponds to the correct location for the installation of Windows you want to repair, typically this will be #1.
5. Type bootcfg /list to show the current entries in the BOOT.INI file. At this point you may get a message telling you that the boot.ini file does not exist. The next step will correct this error.
6. Type bootcfg /rebuild to repair it. This will scan your hard dives for installations of Windows XP, 2000 or NT and display the results. Follow the on-screen instructions to add your Windows installations to the boot.ini file. Those step will be:
1. Total Identified Windows Installs: 1
(1) C:\Windows
Add installation to boot list? (Yes/No/All)
Type y and hit enter
2. Enter Load Identifier
This is the name of the operating system. When you receive this message, type the name of your operating system, and then press ENTER.
3. Enter OS Load options
When you receive this message, type /fastdetect, and then press ENTER.

Note: The instructions that appear on your screen may be different, depending on the configuration of your computer.
7. Take out the CD ROM and type exit.

I believe your hal.dll problem may just be coincidence. Or maybe cause of all the odd letter assignments, Windows just started going

What you can do to test it is just unplug the new drive. If it still shows the hal.dll is missing, it may have just coincidentally become corrupt at the same time you installed the new drive.

If your Windows installation was messed up because a new drive letter was assigned because you added the new drive, I am pretty sure you would have a NTLDR is missing before hal.dll, because hal.dll is loaded after many other Windows files are loaded during bootup. I'm pretty sure the first thing loaded is the NTLDR.

Wadd, I've gone back and forth many times trying different configurations, and it continues to load properly without the new drive plugged in, but fails when it is attached, so it is DEFINITLY that drive that is causing problems... somehow.

Eagle, your response is definitly something I will get to, but like I said, I don't have my XP disk anymore, so I'll have to find a way to get my hands on one first.

Ok, when you do update us please.

Good luck,
Adam

Yeah, that hal.dll problem is wierd. I consulted Microsoft Knowledgebase and hal.dll is the 7th step in the Windows XP boot sequence. Regardless, the original problem of reassigning drive letters still exists. I'll definitely keep tabs on this and do some research. It is a pretty interesting subject.