All of a sudden “operating system not found”

[the wopster]

All of a sudden I have got a “ operating system not found” message when booting does anyone have any idea what could have happened and how I can rectify it

 

[scubes]

Maybe your hard disc ssd has failed .

 

[stockhausen]

Get into the BIOS setup (typically "Del" or "F2") when the system is starting up and see if any HDD is apparent.
Another "issue" I have encountered is that sometimes a system will not boot when you have a USB Memory Stick plugged in.

 

[Glanza]

Drive failed or your bios has reset possibly changed from UEFI to legacy or vice versa.

 

[smogsy]

Could be faulty SSD/HDD but more likely its a corrupted bootloader

if the bios does not show a Windows system in the Boot options most likely its BL issue


Bootloader fix:
Boot up the Recover Windows image (you can create one in windows with ease)

Boot it into the recovery CD -> Go to repair - > Command line ->
bootrec /FixMbr bootrec /FixBoot bootrec /RebuildBcd

this will fix any bootloader issues once done retry booting into windows

if you need more instructions
https://www.groovypost.com/howto/fix-windows-10-wont-boot-startup-repair-bootrec/