For the simplest current solution, I'd hit eBay and grab XP. I am guessing that XP is getting more expensive these days as people who have a copy know that they control the supply and that no more will ever be available.
Isn't eBay a bit dodgy? What happens when it won't activate and you phone Microsoft and explain that you bought it off eBay? Are they likely to be sympathetic?
If you have the certificate of authenticity, then they can't really question you besides to provide proof of purchase (which is the certificate of authenticity).
That's the part people often refuse to send, though.
Yeah.... well can't really do anything about that though. It is the proof you own the key. Without it, you're out of compliance with the EULA from microsoft.
Yup, understood, but that is the dodgy bit with a lot of resellers. They sell everything but the part that matters.
well if you buy that, that's on you - it's the only part that matters in most cases, I have a dozen XP CDs lying around, the license is another story.