This QSN is presumably related to me as a present owner of Vegas 5 + DVDA. However the QSN isn't the SN of those packages. Where do I find the needed number?
The qualifying serial number is your old serial number, if you are upgrading from Vegas+DVD then you would enter your DVD Architect serial number. If you are getting an error that the number is not valid then most likely you are entering an activation code and not the serial number. If you are set up for My Account you would be able to find your serial number there.