Hello, I'm writing a program and now trying to find a way to check to see if a Windows XP CD-Key is valid. Obviously the algorithm is not known, but is there an API call in Windows that could do ...

Hmm, Windows 7 DVD won't boot, XP CD won't except its installation key. Hmm, what could be the common culprit here? My first suspicion would be the optical drive or the CD/DVD.

Want to reuse your existing Windows license key with a new PC? We explain how to determine if that’s possible.