Hi Just interested if anyone has any thoughts suggestions or help. So I had parallels 10 and windows 8.1 decided to upgrade to windows 10. Clean installed windows 8.1 and then updated to windows 10 Activated. File size of the virtual machine is 35gigs!!!!! - No additional software just the OS. Removed the virtual machine and backed it up. Tried to install windows 10 fresh and then have it activated via hardware registration New clean install virtual machine is 10gigs BUT can not activate Any thoughts or suggestions, quite like having windows as an option but not at that file size.