Question Changed boot setting to UEFI can’t boot anymore

[MoonWobble]

I made the very unfortunate error in changing my BIOS boot options to UEFI without having the proper UEFI storage set up and now (obviously) my computer won't boot, I can still enter my BIOS at least. I had changed the secure(?) boot setting from “Other OS” to “UEFI”. I have since changed it back, but with no luck. Is there a way to do this without reformatting anything?

I have also taken out the CMOS battery for maybe an hour, I’m going to try and leave it out for longer and also unplug my machine in the meantime.

I’m freakin out. All help muchly appreciated!

Edit: parts

Intel Core i7-10700K 3.8 GHz 8-Core
Asus PRIME Z490-A ATX LGA1200
G.Skill Trident Z RGB 32 GB (2 x 16GB) DDR4-3600 CL17
And a 1000W PSU

 

[SkyNetRising]

Is there a way to do this without reformatting anything?

Show screenshots.
(upload to imgur.com and post link)

Show, what you changed in BIOS.
Show error, you're getting, when trying to boot.

List full specs of your system.

 

[MoonWobble]

Show screenshots.
(upload to imgur.com and post link)

Show, what you changed in BIOS.
Show error, you're getting, when trying to boot.

List full specs of your system.

Just got off the phone with microcenter, they advised I reseat my RAM. Which I tried and must have messed up or something somehow because now it won’t even get to BIOS with an orange light on my MOBO. Otherwise I would. Will update if I can get anything back up and running

 

[Plicker19]

I too have experienced this issue before. Have you enabled secure boot, if there was an option for it?

 

[MoonWobble]

I too have experienced this issue before. Have you enabled secure boot, if there was an option for it?

I’m not sure if I did or not, what I do remember now is that I changed in the boot setting was OS type to “Windows UEFI mode” from “Other OS”. The “Secure Boot state” option was greyed out so I couldn’t change it anyway, but I believe it was disabled

 

[Plicker19]

I’m not sure if I did or not, what I do remember now is that I changed in the boot setting was OS type to “Windows UEFI mode” from “Other OS”. The “Secure Boot state” option was greyed out so I couldn’t change it anyway, but I believe it was disabled

Hmm, usually when secure boot is greyed out, it indicates that UEFI is enabled with BIOS/CSM compatibility, meaning that it will not be exactly compatible with a standard GPT disk that is looking to boot with a UEFI native BIOS. Is there a "native" UEFI option in your BIOS setup menu?

 

[MoonWobble]

Hmm, usually when secure boot is greyed out, it indicates that UEFI is enabled with BIOS/CSM compatibility, meaning that it will not be exactly compatible with a standard GPT disk that is looking to boot with a UEFI native BIOS. Is there a "native" UEFI option in your BIOS setup menu?

I’d love to check but my PC is currently not getting to BIOS, there’s an orange light on my mobo, after regrettingly trying to reseat my RAM

 

[Plicker19]

I’d love to check but my PC is currently not getting to BIOS, there’s an orange light on my mobo, after regrettingly trying to reseat my RAM

My bad, I thought you were still able to access your BIOS. What is the brand of your motherboard?

 

[MoonWobble]

Hmm, usually when secure boot is greyed out, it indicates that UEFI is enabled with BIOS/CSM compatibility, meaning that it will not be exactly compatible with a standard GPT disk that is looking to boot with a UEFI native BIOS. Is there a "native" UEFI option in your BIOS setup menu?

Thank God a green light, let me find out now.

 

[MoonWobble]

My bad, I thought you were still able to access your BIOS. What is the brand of your motherboard?

So a quick look into BIOS using the search function and “native” only brings back:

PCI Express Native Power Management=Disabled
And
AMI Native NVMe Driver Support=Enabled

Also my “Secure Boot State” = User

 

[Plicker19]

Perhaps different companies use different terminology... what BIOS boot options are present? (i.e. legacy, uefi, hybrid, etc.)

 

[MoonWobble]

Perhaps different companies use different terminology... what BIOS boot options are present? (i.e. legacy, uefi, hybrid, etc.)

The only two options are,
“Other OS”
“Windows UEFI mode”

Of which the former was my original setting when everything was still working. It’s back on that setting right now as well.

 

[Plicker19]

The only two options are,
“Other OS”
“Windows UEFI mode”

Of which the former was my original setting when everything was still working. It’s back on that setting right now as well.

As SkyNetRising asked before, what are the error messages that appear when you try and boot from each BIOS mode?

​

 

[MoonWobble]

As SkyNetRising asked before, what are the error messages that appear when you try and boot from each BIOS mode?

​

Recovery


Your PC/Device needs to be repaired


The operating system couldn't be loaded because the system registry file is missing or contains errors.


File: \Windows'system32\config\system


Error code: Oxc000000f


You'll need to use recovery tools. If you don't have any installation media (like a disc or USB device), contact your PC administrator or PC/Device manufacturer.


Press Enter to try again


Press F8 for Startup Settings

 

[Plicker19]

Recovery


Your PC/Device needs to be repaired


The operating system couldn't be loaded because the system registry file is missing or contains errors.


File: \Windows'system32\config\system


Error code: Oxc000000f


You'll need to use recovery tools. If you don't have any installation media (like a disc or USB device), contact your PC administrator or PC/Device manufacturer.


Press Enter to try again


Press F8 for Startup Settings

Ok, are you able to enter Startup Settings and select "command prompt" after selecting "advanced?"