What version you have? Us or Eu? I could most likely get you the right file, but I do need Credits. If that's .. Legal here? No warns please. :S
Someone suggest putting the cd 1 in and choose reapair. Then you can uninstall. Or you could go to the WOW folder and delete it. Then delete it from your registry.
He says he doesn't have the CD's? I dunno, I was just telling them to try what I was suggested. If all else fails chill out and go to http://us.blizzard.com/support/article.xml?articleId=21049 and send them an email. i hate suggesting things I don't try myself first.
I used the repair, and I still got the message. Edit: I deleted all the files, and I think I removed all traces of it in the registry. Edit again: Cleaning with CCleaner now. Edit now again: Works like magic, thanks all!