Once you are logged in your software unlocks all Pro Infinity features. You can login using your VDJ Forum ScreenName or your registered email address - the password is the same for both. Login Process When you open Virtual DJ 8 for the first time you will be presented with a Login Screen. You can have both machines running at the same time in case of an error with your main machine. But this basic: You can install VDJ8 on two machines (per Pro license). I'm not going to get into EULA - you can read that here. Virtual DJ 8 - Login and License Virtual DJ 8 requires a login in order to verify your license, rather than using a serial number or license code.