I bought 2 copies of Norton system works and firewall for my 2 computers. I mixed up the CD's and registered the same product key twice. now neither one works. I can only find one of the system works CD's but I still have both product keys from the CD jackets. Do I need to reinstall everything? Can I use the one CD for both installations and register or activate under the correct product keys? Or is the product key also embedded in the CD? I'm so afraid to do anything. One computer crashed in January after I downloaded a Norton upgrade. I probably didn't do it right. I don't want to lose another computer. Thanks so much for your help.