Windows XP Snafu

Two weeks ago, my laptop had a physical hard disk failure. I was forced to order a new one, so I took the opportunity to upgrade to a new high-performance disk. New disks come blank, of course, so I needed to go through the process of setting up the operating systems again. Since I decided to dual-boot Windows XP and Windows Vista, XP had to go on first. I’ve performed this procedure several times before, so I expected it to be quick and painless. However, what happened was something completely unexpected for me.
Windows XP did not take the product key printed on the back of my laptop.
Apparently, there are three separate versions of Windows XP Professional: Retail, OEM, and Corporate. I had a retail disc and an OEM key, and the retail key for that disc had already been used. Now that’s a real showstopper.
I called up Microsoft technical support. I was greeted by a man with a thick accent, who asked for my name and phone number. I gave those to him, then explained my situation. It took a few tries to get the man to understand what my problem was, but he finally caught on and transferred me to the licensing support department. They confirmed my contact information a second time, which turned out to be wrong, so I had to correct them. I asked them what I could do to get my Windows running again, and to my surprise, they said that each Windows disc has its own unique key and the only disc that would work is the one that came with my computer.
First of all, that is not true: any key will work with any disc as long as they are of the same version listed above. Secondly, I don’t have my original disc with me, because if I did, I wouldn’t have called Microsoft for help.
Next, I called the Cornell Store to see if they had an OEM disc lying around. They told me that they did not handle Windows installs. Interesting; I didn’t know that about the Cornell Store.
Then, I tried calling CIT to see if there’s anything they could do. The guy at the other end apologized for not being able to help, but then asked me for my NetID before hanging up. Why does CIT need my NetID if there’s nothing they can do to help? And how dare they ask for it after giving me bad news?
All that time wasted, and I’m still on square one. Fortunately, Microsoft recognized this huge design flaw and corrected it for Windows Vista: you may install any version of Windows Vista using any given disc, provided you have the key for that version.