I'm having the same problem. I removed the virtual machine and reinstalled windows 10. However, still got failed EFI hard drive wait 30 then 60 seconds.
followed by EFI Shell 2.31. Typing exit did not solve the problem. I install from windows 10 home usb drive full version from Microsoft.
The simplest way to do a fresh installation of Windows 10 on Parallels Desktop, download the ISO from http://bit.ly/1LT6FpT and install Windows 10 as per the steps given in the articlehttp://kb.parallels.com/4729I'm having the same problem. I removed the virtual machine and reinstalled windows 10. However, still got failed EFI hard drive wait 30 then 60 seconds.
followed by EFI Shell 2.31. Typing exit did not solve the problem. I install from windows 10 home usb drive full version from Microsoft.