In T148703#2019487, @Lex wrote:

@John343 Hi. You upgrades Win 8.1 to Win 10. This is a bad option for the error "0xCFFFFFFF - STATUS_APPLICATION_HANG". This error is due to damage to system files. You need to check the integrity of system files or a clean installation of Win 10.

In T148703#2019473, @Vitdom wrote:

You should be able to close down DayZ without rebooting using a second desktop through the WindowsKey + Tab keyboard shortcut if Ctrl + Alt + Del doesn't work.

Try renaming your DayZ Documents folder.

This is the worst problem I have had playing any game in 20 years of PC gaming. It throws no errors, is reproducible across an major major upgrades, Win 8.1 to Win 10 and GPU from Radeon 7970 to Radeon 5700XT. Yet experimental with Livonia worked. I don't like asking for help but there it is.