Windows 10 would not reboot after auto update

[Determinator]

I run a dual boot machine with Windows 10 and WIndows 7, both Pro.

After on restart after Windows 10 updates, the machine would not even give me a boot menu to select the OS to start. Instead, it kept beginning the boot process, then shutdown, then tried to restart again... over and over and over...

In desperation, I tried powering off and disconnecting the hard drive for the Windows 7 OS then restarted Windows 10 normally. After shutdown, I reconnected the WIndows 7 drive and restarted normally.

Anybody seen anything like this ? Is there a way to avoid little "surprises" like this ?

 

[Colif]

So you have a win 10 installer? Do you want one? Get it here: Win 10 media creation tool

if this happens again, change boot order so USB or DVD is first, win 10 boot drive second
boot from installer, on screen after language choices, choose repair this PC, not install
choose troubleshoot
choose advanced
choose start up repair - this will scan pc and maybe fix the boot menu, will ask for logon info

another thing to try is boot into safe mode
use installer again and choose repair pc again
choose troubleshoot/advanced
Choose start up options
pick one of the three safe mode choices, doesn't matter which
pc restarts in safe mode. you don't have to do anything, just restart and see if it is fixed.

Could also look in BIOS and see what Boot method you have set, I assume its auto since you potentially have both GPT and MBR discs in PC