Separate names with a comma.
I was able to upgrade to Windows 10 Pro from Windows 8.1 Pro (running Parallels 10 via OS X 10.10.4/iMac) by using Windows Media Creation Tool...
I have Parallels 10 installed on a Mid-2010 iMac and had Windows 8.1 Pro Upgrade version installed. I had the same problem with the "cannot...