I'm running Windows 7 with Parallels 8.0.18619. When I first attempted to install Yosemite (10.10.x), the installation stalled. I immediately tried a 2nd time and that time it installed fully. I've been using it now for about 2 weeks with very little problem. There ARE some things that don't work properly in OS X. I think it may have ruined my "Time Machine" installation or maybe not. I did just buy another backup disk (Passport 1 TB for OS X) which is now working fine. My "Snagit" program doesn't work anymore. In Parallels, everything seems fine although to be truthful, I haven't had a chance to run every Windows program. Excel for Windows works fine. I'm able to printer wirelessly from both OS X and Win 7.
I DO miss my Snagit though.
I probably should have stated that I ONLY installed Yosemite over Mavericks and didn't alter my long running Parallels 8.x.x.
Last edited: Jun 16, 2014