Black screen with flashing underscore after changing a case fan?

[Killah1435]

I recently changed my rear case fan because it was making rumbling noises, and when I plugged everything back in and went to boot it up, I was greeted by a black screen with a flashing underscore, I can get into the BIOS and it notices both my HDD and my SSD and the boot priority is normal, but it will always boot to the black screen with flashing underscore, could use some help

 

[Colif]

it probably happened cause of way win 10 shuts down now and isn't actually off unless you unplug it.

do you have a win 10 installer? On another PC, download the Windows 10 media creation tool and use it to make a win 10 installer on USB

try this:
Start up repair
change boot order so USB is first, hdd second
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose start up repair - this will scan PC and maybe fix this - will ask for logon info

if that doesn't fix it, try loading into safe mode
boot from installer, on 2nd screen after languages, choose repair this pc, not install
choose troubleshoot
choose advanced
choose start up options
hit the restart button
choose a safe mode (it doesn't matter which) by using number associated with it.
Pc will restart and load safe mode

sometimes just booting into safe mode is enough to fix this up. Restart PC and see if it boots normally

try those 2 and see how you go