New to here and having a problem

I just bought dvdfab online and for some reason when I try to enter the code it doesnt respond. The stupid thing just keeps me on the free trial version . ps i am very inept with computers so if anyone could help me i would be very thankful

Are you typing the code or coping and pasting? When i first installed the program i copied and pasted but when i copied i also copied the space before the first character, this is then pasted making the key invalid. Make sure you have only the key when you copy no spaces at the being or end. I hope your problem is as simple as mine was.