Hi, I installed Yosemite 10.10.4 (clean install) 2 weeks ago. So as my virtual machine Parallels Desktop 10 was old with many programs, I reinstalled my Windows 8.1 Pro 64 and only programs I am now using. My Windows activation is done and all is OK. All updates are done and no problems with Parallels Desktop 10 : but so many problems with Safari Yosemite and I'd like to downgrade to Mavericks with clean install with USB Key. But what's about my Windows 8.1 activation?? Do I have to re-activate or can I save and restore my activation key?? Always calling for activation and bla... bla... bla... Many thanks for a response and sorry for my poor english. Have a nice day.
@GRYBEKJ Hi, Yes, you need to reactivate your Windows 8.1 virtual Machine again. If you are getting an error " Can't activate" Please refer http://kb.parallels.com/113879 and let us know how it works. Thanks!