Convert Windows 10 from Legacy BIOS to UEFI without Data Loss  

You have always been spot on and I appreciate our help. So much gets lost in writing rather than speaking.
I did run system information and am in UEFI. That and checking GPT were the first two things I did when I got this.
I agree I cannot enable secure boot in legacy mode that is why I am trying to find out how to disable legacy and enable secure boot. Once there I wanted to know how to gt back to legacy. Videos/readings I saw look nothing like this z 390 by Asus. so I cannot even guess at choices to get to enable secure boot. I knew you had to disable legacy then enable secure boot but these settings are not obvious.
I bought Window 10 Pro and had him install it. I did not know it would be legacy.
I asked him some questions but he is not rally helping me solve what I ask.
I think I may ask if he would show me while I take notes even at a tutorial cost. I've run out of resources.

PS I hope I can perform a clean install when I want - he maintains the PC is just like the old BIOS one while in legacy and UEFI.
I can see removable media when I am in the firmware settings and in the boot settings.

To go to legacy boot mode would require you to re-partition your hard drive/ssd as MBR. That either requires software you have to pay for; or you can back up your current system, erase the hdd/ssd and make it MBR, then restore the backup files to it. In addition, you may have to recreate a system partition. It's not something a novice would want to tackle.

The only reason to enable legacy boot mode on a UEFI system is to boot from an older operating system that cannot be set up to boot in UEFI mode. You don't seem to have that requirement.

Maybe in your UEFI settings, legacy mode is called CSM. If you see options for CSM in your UEFI settings, disable that, and then you should be able to enable secure booting.

The information you want is on page 2-23 & 3-24 of your motherboard user's manual (English language).

It appears switching between legacy and non is not a viable idea.

If I bought a new PC wouldn't it be UEFI without legacy and secure boot enabled?
Maybe booting without legacy is difficult so he did me a favor by using legacy.
I would think with my limited knowledge, I should have UEFI and secure boot with no legacy. Then he could show me how to boot from removable media, ex, disable secure boot, set up boot order with desired device at top.
The alternative is to leave as is..

I understand thank you for all the help

Hello,
I'm new to the forum. My brother purchased a new motherboard over a year ago, we just installed it last week.

The BIOS was old and missing some menus, Windows installed in Legacy mode due to the missing setup menu selections. I used the above Option One and the conversion to UEFI was successful.

However, a new drive "F" partition on the "C" drive was created and also shows up in "This PC" / Devices and Drives. Also, Disk 0 which was the "C" drive is now the "E" drive, which is a SSD data drive.

I want to remove the "F" drive from This PC / Devices and Drives. Can I delete the "F" drive partition on the "C" drive?

Two screen shots below:



Thanks

Okay, thanks Shawn. I'll try this tonight.