Operaguy, To me, a purchase order number is the same difference as a serial number. The only way to login for free updates or purchase upgrades is to enter that number. To install the software, no number is required. If there are suddenly lots of logins on a specific number, then it obviously is compromized. Then the vendor should contact the purchaser, inquiring about the situation. The warez community may distribute the number, but it will only be valid for a very short time. The only way I see to make a serial number truly secure is to customise each copy of the program to only install with that specific number. And that still won't stop the warez hackers. Now, I realise that no system will be perfect, but I disagree with making legit purchasers jump through hoops. And that is really all I wanted to point out :)