Try signing out and back in to the Splice app. When using Splice RTO, you should not be asked for a product key for Serum. Since you are, this means one of a few possibilities: - you had previously installed an old copy Serum on the computer and it is (now) running - Splice has not deposited a license on your computer (e.g. download / update Splice app and log in) <- very likely if 'new computer' - Splice has revoked a license from a failed payment (?) <- very likely if it worked prior.. Keep in mind you need to be connected to Splice app online at least once every 3 days. Once you have paid off Serum this is no longer needed. (windows) You can go to C:%localappdata%Splice and verify you see a Serum.lic file Also, here's boilerplate message from Splice (and me I guess now!): ---------------- Please make sure you have deleted any previous versions of Serum you have on your computer. Then confirm that you are signed into the Splice app (the Splice logo will appear in your menubar) and have the latest version of the Splice client installed. The current version for OSX is 2.1, and for Windows it's 1.2.15. If you need to download the Splice app, you can do so here: splice.com/download If you need to re-install Serum, open the client and navigate to the 'Plugins' Tab and click 'Reinstall'