I would login into my account at MyPresonus, click the software tab up top. It should list the Studio One version you have. Click on 'View More Details' right below it. Under the Licensee it should have the options, Offline Activation, Transfer License, 1/5 Activations-Manage. Click on the '...Activations-Manage'. You should be able to unactivate previous installs so you can register it. I hope that helps.