Brand-new to Parallels. A few months ago, I did the "try for 14 days" option, which installed a technical preview of Windows 10. Today I purchased and downloaded Parallels 13 but it won't start because Windows 10 technical preview is expired. "Recovery" screen appears. I want to completely obliterate the older version of Parallels / Windows 10 that seems to already exist on my machine so I can start up Parallels and let it guide me through the Windows 10 installation. Any advice?