Grapher 12, Surfer 13, and Strater 5 each have two versions: a product key version and a serial number version. If you are getting an error ("The product key entered is not valid" or "Invalid serial number. Please re-enter serial number") when you enter your product key or serial number, it's possible you have the wrong version installed.
If the value you're entering is short (fewer than 15 characters), you have a serial number. To activate the program with a serial number, you need to have the serial number version installed. The dialog where you enter the serial number looks like this:
If the value you're entering is longer than 15 characters, you have a product key. To activate the program with a product key, you need to have the product key version installed. The dialog where you enter the product key looks like this:
If you have the wrong version installed, you can easily remedy this by downloading the correct version from My Account. The most updated version required for your serial number or product key will be downloaded automatically when you click the download button next to that serial number or product key.
Updated December 18, 2018