@Michael-Malloy6896 Are you trying to use a different e-mail address than before? The software is perhaps already registered to a customer account with a different e-mail address. The software is now bound to that account and cannot be registered to another account. If you want to use a different e-mail address you first need to visit Magix.com and log into the account using the old e-mail address and change it in the account settings.

If you're sure that you use the correct e-mail address it might help to deactivate previous installations of your Sound Forge 17 in your customer account. For this, look under 'My Products' in the account settings, select your Sound Forge 17 product and deactivate the installation. Then try to activate it again on your computer.