MS only allow you to use their Product on ONE PC (for Normal Home Users, not Multi party License etc etc etc.
When you called them you admitted you were trying to use it twice. NAUGHTY YOU !!!
CANNOT believe they Wiped your disc though???????????
That is incredible Illegal............Because you HAD NOT actually loaded their software twice...........You Only tried. CONTACT THEM, they will put you right or probably deny all knowledge.
Go to ebay and try to buy Legal Copy of XP