When you purchase a Norton antivirus online or from a retail store, you receive a product key to activate your product. You get it as a card if you have purchased it from a retail store. And if you have purchased the product online, you will receive an activation code on your registered email. You need to enter this code to unlock all the paid features of Norton Antivirus, but the product key may not work. In the post below, you will learn about this issue's possible causes and solutions.
Incorrect product key: Most people face this issue if they mistakenly enter the wrong product key, like some characters, such as the number 0 and the letter O look similar.
The product key needs to be activated: You can face this issue if you have purchased the Norton from a retailer and he has not activated it.
Used product key: If the product key has previously been used by someone else, then your product key won't work anymore.