Stuck with XP without a key

Hello, since I'm posting, its probably obvious I have a problem. My computer runs XP, but I accidentally installed a new XP pro. The problem is that I don't have a key for the new XP pro, so I can't even log on. Is there a way to uninstall this XP back to my original XP? My computer was refurbished, so I don't have the installation CDs for the original. Am I screwed?

 

You mean you don't have a product key? How did you finish the install without a product key? As for going back to your original XP, it's probably impossible at this point, but I guess it would really depend on how you installed the Pro version, and whether it is an upgrade CD. If you did a repair install "on top of" or "over" your original XP, or if you did a clean install, you're probably 'screwed'. If you did an upgrade (and it's an upgrade CD that you installed from), there might be some hope... but don't bet on it.

How do you 'accidentally' install an operating system?

 

Yes you are screwed as you put it. If you don't have a product key or discs then you won't be able to reinstall or activate windows.

Your pc may have a recovery partition so you may be able to recover the old operating system however without the product key you still wont be able to activate it. You will have check this. You could have got the old product key from the windows registry before you wiped the old os but now that you have reinstalled windows it is impossible to recover.