Updating to Windows 11 (Secure Boot, CSM problem BIOS)
Updating to Windows 11 (Secure Boot, CSM problem BIOS)
Hi - I'm trying to switch to Windows 11 finally. I think I have everything the right equipment for, like the B660M Pro RS and Intel Core i5-12400F. I've already turned on Secure Boot, but now I'm still stuck in CSM mode. When I turn CSM off, my Windows 10 installation drive isn't being detected at all. Originally, I enabled CSM from the BIOS so I could boot with my old drive, which worked perfectly—but now it's preventing me from upgrading to Windows 11. My storage is a Kingston SSD with 480GB and NTFS file system. If the fix requires replacing the SSD, it shouldn't be too big of a problem, but I'd prefer something faster. Could anyone assist me? Thanks.
As I believe this shows, my C drive is NTFS. The 32 GB one is just a basic data drive. Thanks
So it's a problem with the partitioning? Thanks (I just set this up normally with Windows 10 install)
What is this 32GB storage? It seems like a USB flash drive. It includes an UEFI bootloader. You can either remove the drive or delete the 99MB EFI system partition from it. These steps will remove the partition from the 32GB drive.
Using diskpart:
list disk
select disk 1
list partition
select partition x
(select 99MB EFI system partition, x=2 or x=3)
delete partition override
To make your OS drive UEFI compatible, follow these actions:
Run a validation check from the elevated command prompt.
mbr2gpt.exe /validate /disk:0 /allowFullOS
If the check passes, proceed with conversion.
mbr2gpt.exe /validate /disk:0 /allowFullOS
Then enter BIOS, turn off CSM, and set the first boot device to Windows Boot Manager.
The 32 GB one is essentially just a 'data' drive with some regular photos and files on it. It seems somewhat unnecessary, but I wonder why it wasn't disabled earlier. I believe disabling it in the boot-up section of 'BIOS' was the right approach. Watching the video on MBR confirmed this, as my C drive matches what you described. The bootloader behavior is unusual—it often attempted to launch Windows from there, which I didn’t pay much attention to. Disabling it at startup seems sensible. I think I should proceed with the MBR procedure first. That’s the main step.
This time it worked perfectly. I'm fully operational in UEFI mode, no longer using CSM or legacy settings. My PC Health Check confirms everything is fine, and I can proceed to Windows 11. That's incredibly great! Your guidance has been amazing and your instructions clear and helpful—feel free to adjust if needed. Thank you so much! You're truly exceptional!