Interestingly I get the same "boot failed" error with Parallels 10.3. My VM (10.10.5 Server) ran fine until the update from Parallels 10.2.2 to 10.3. Reinstalling Parallels 10.2.2 didn't help, as the VM became unusable. Recovery Mode > Disk Utiliy did not find any errors. I was able to get a older VM backup running with Parallels 10.2.2. Now I tried to upgrade a copy of my VM to OS X 10.11 with Parallels 10.2.2. It looked promising, but about 4/5-ths into the installation, the progress bar stopped. It reminds me of the problems with Parallels and OS X 10.10 one year ago. I seems as if Windows is more thoroughly tested than OS X at Parallels.
So, I am typing this from the El Capitan GM Candidate running in Parallels 11 on an El Capitan Mac. This also worked under Yosemite, both within Parallels 10 and 11. I actually installed the GM Candidate version on Parallels 10 in Yosemite, and just upgraded // to 11 and then installed // Tools. I have not tried building a new El Capitan (beta or production) under 11. The thing that disgust me a bit under 11 is that, under 10 and previous versions, the license seemed to allow you to install on a desktop and a laptop. Not, it really means 1 host, so I have had to buy two upgrades. Not happy about that at all.
Each time I start Windows 10, I get the Operations Timeout error. I tried everything described in your Article ID: 116216 Created On: Jun 3, 2013 Last Review: Apr 3, 2015 Still have the problem Windows and OSX are up to date Any way of fi
after el cap upgrade I could not get version 10 to work. I then bought and installed version 11. Is there some trick here. It is almost unusable now, sooooo slow www. Is there an easy fix or did I waste 60 dollars