Hello ArielI, For Parallels Desktop, it's always one license per Mac. The corresponding number of licenses must be purchased for the corresponding number of hosts. Please refer to http://kb.parallels.com/112971 for details. We have reset the Parallels Desktop 11 license key. kindly try to activate it. If the issue still persists, please execute the following command with Terminal < prlsrvctl activate-license-online >.