I have installed the latest parallels and latest Mac OS and the latest windows 10 updates and the first time I run parallels after rebooting (or turning on) the MacBook the windows startup fails and says windows did not appear to start correctly. It suggests rebooting windows which on the second attempt is successful. And will be fine until I power cycle the Mac. Something in parallels is not initialising first time after the boot.
Hello Matt20. Please shut Windows down properly (as opposed to stopping it), quit Parallels Desktop and reboot the Mac. Does the issue occur even now?