I've spent days installing my old MacOS (Mavericks) on an external SSD prior to cloning back to my Mac as a leaner meaner quicker system. The time is taken up by copying across all my applications (I have many) with their support folders and preferences. Some applications launch straight off but some require the licence key again. The problem is with my old version of Parallels (10) whose VMs currently run fine on the Mac. I've tried to find the activation key for it but it is nowhere to be found, nor is it displayed in 'About Parallels' window. The new system will require me to reactivate Parallels. When I originally activated and registered my copy, I had an email address which has since been discontinued as that ISP doesn't do emails anymore. I've told Parallels about this several times but though this account here is with my new email, as far as my app is concerned Parallels have ignored all attempts to change my registration details with them. I need to find out what my activation key is. Can anyone help? (No, I've no intention of upgrading from Mavericks. I'm prepared to buy a newer version of Parallels but apparently in order to activate your existing VMs you have to provide your old activation key, so the whole thing is a nightmarish Catch-22 situation. Why do Parallels make activation so difficult???).