The most common location is a bright orange or yellow sticker on the inside of the CD/DVD jewel case. If you bought a retail box, the key is often printed on the back of the quick-start guide or on a separate card.
"Please enter a valid serial number or product key." vidbox vhs to dvd 9.0 deluxe product key
Users who registered their product can have their keys recovered by customer support even years later. The most common location is a bright orange