https://www.tenforums.com/tutorials/81502-convert-windows-10-legacy-bios-uefi-without-data-loss.html
1 Open a command prompt at boot. 2 Copy and paste the mbr2gpt /convert command into the command prompt at boot, and press Enter. (see screenshot below) 3 When the conversion has successfully completed, you will need to boot to UEFI firmware settings, and switch the firmware to boot to UEFI mode instead of Legacy BIOS (CSM).

https://www.youtube.com/watch?v=VtJp1RG45eM
Upgrading to UEFI BIOS has many benefits, incl... "In this tutorial, we'll show you how to easily convert your legacy BIOS to UEFI BIOS without losing any data.

https://helpdeskgeek.com/windows-10/how-to-change-bios-mode-from-legacy-to-uefi-without-reinstalling-windows-10/
In the app, right-click on the disk on which you've installed Windows and select Properties . Next, you want to check your disk partition style to confirm whether you're running the Legacy BIOS or UEFI. If you're using BIOS, your disk partition style will be MBR. If you're already on UEFI, the disk partition style will be GPT.

https://forums.tomshardware.com/threads/can-i-change-bios-from-legacy-to-uefi-without-loosing-data.3724834/
But before you use it, make sure your system supports UEFI. If it doesn't, then you'll be screwed big time. No easy way for reverting back. Only restore from backup or use of advanced 3rd party partition management tools and manual bootloader recreration.

https://www.maketecheasier.com/convert-legacy-bios-uefi-windows10/
Right-click on the Windows installation disk, Disk 0, and select "Properties.". In the Properties Window, go to the "Volumes" tab. If you see "Master Boot Record (MBR)" next to "Partition style," you are on Legacy BIOS. If, on the other hand, it says "GUID Partition Table (GPT)" as in the image below, then you're already

https://www.makeuseof.com/windows-10-11-convert-legacy-bios-uefi/
Once the disk is validated, execute the following command to complete the conversion. Windows should now begin the conversion process. Wait patiently for the process to complete and then reboot your PC. Upon rebooting, launch the firmware settings screen for your motherboard and switch it from Legacy BIOS to UEFI.

https://geekflare.com/change-bios-mode-from-legacy-to-uefi/
Check the current status. Type System Information in the Search bar and click open the appropriate result. There you can check the BIOS Mode is showing Legacy: You can also confirm this with the disk type. Press Windows+R, type diskmgmt.msc, and click OK. This will open the Disk Management console.

https://www.minitool.com/partition-disk/convert-legacy-to-uefi.html
Shut down your PC. Power on the PC and press the BIOS key (Del, Esc, F2, etc.) immediately when the PC brand logo appears. You can see the BIOS key at the bottom of the PC logo screen. Or, you can search for it online. Now, you are in the firmware. Go to the Boot tab and change the Boot Mode from Legacy to UEFI.

https://www.tenforums.com/tutorials/81502-convert-windows-10-legacy-bios-uefi-without-data-loss-31.html
Please see OPTION TWO To Convert Windows 10 from Legacy BIOS to UEFI at Boot - this is done from the Cmd Prompt at boot - labelled the X -prompt as shown on the image under that heading which is the same as using a WinPE boot disc, made as below. WinPE in the context of the tutorial may be referred to as the Windows recovery environment cmd

https://windowsloop.com/convert-legacy-bios-to-uefi-windows/
Open the start menu, search for "Command Prompt", right-click on it and select "Run as administrator" option. In the Command Prompt window, execute the below command. mbr2gpt /convert /allowfullOS. As soon as you execute the command, Windows starts the BIOS to UEFI conversion process. If the command is successful "Conversion completed

https://www.diskpart.com/windows-10/convert-windows-10-from-legacy-bios-to-uefi-without-data-loss-7201.html
3. Click on "Apply" to commit the pending operation. Then the computer will finish the operation in Win PreOS mode. Step 2. Convert Windows 10 from Legacy BIOS to UEFI. After you have converted the Windows 10 system disk from MBR to GPT, now need to reboot the system, boot into BIOS and select UEFI firmware.

https://answers.microsoft.com/en-us/windows/forum/all/convert-an-existing-windows-10-installation-from/aa8c2de3-460b-4a8c-b30b-641405f800d7
Step 4: Change the boot order in firmware Settings. Now to boot from GPT, the settings in the firmware need to be changed. Boot to the PC's firmware settings, and do the following: Boot method: UEFI from Legacy. UEFI-CSM: Disabled. Secure Boot: ON. The boot order would usually show Windows Boot Manager at the top.

https://www.easeus.com/partition-manager-software/change-bios-mode-from-legacy-to-uefi.html
Open the BIOS setting to choose UEFI as the boot mode. The general procedure is as follows, although some details may vary by the computer manufacturer. Step 1: Turn on or restart your computer. Step 2: When the computer manufacturer logo interface appears, long-press F2 to open the BIOS Setup.

https://recoverit.wondershare.com/windows-tips/convert-legacy-to-uefi.html
How To Convert Legacy BIOS to UEFI Without Data Loss on Windows 10. The conversion is not that complicated. Using a Windows tool named MBR2GPT, you can quickly convert legacy BIOS into UEFI. Before installation, verify that: You have backed up all the critical data on portable device storage;

https://www.youtube.com/watch?v=A4uEsafUvNQ
In this tutorial I'm going to show you How to Convert LEGACY BIOS to UEFI BIOS Windows 10 without Data Loss. By using this guide you can easily able to chang

https://www.tenforums.com/tutorials/81502-convert-windows-10-legacy-bios-uefi-without-data-loss-11.html
Brink said: I noticed that your "Active" partition is on Disk 1 instead of Disk 0. As a test, disconnect Disk 1, 2, and 3 leaving only Disk 0 connected to see if you're still able to boot into Windows 10 and convert to UEFI. If you can't boot, then you could see if running a Startup Repair may allow you to afterwards.

https://www.intel.com/content/www/us/en/support/articles/000024558/memory-and-storage/intel-optane-memory.html
Open Command Prompt with administrator privileges. Run the following command: mbr2gpt.exe /convert /allowfullOS. Restart the system and boot into the system BIOS. Change the settings from Legacy BIOS mode to UEFI mode. Alternatively, you may also run this command from the Windows Recovery Environment: Boot into the Windows Recovery Environment.

https://www.youtube.com/watch?v=9dMAXgwi5to
#windos11 #windows10 #legacybios #uefi #uefibois #converttouefi #uefiwithoutdataloss #uefiwithoutreinstallingwindows #mbr #gpt #legacy #uefi In this video i

https://www.redhat.com/sysadmin/bios-uefi
At this point, I'd recommend rebooting your system to verify that your BIOS-based machine can boot the freshly converted GPT disk. Here's what the disk now looks like: This can also be seen from the shell: [root@localhost ~]# fdisk -l /dev/sda. Disk /dev/sda: 119.24 GiB, 128035676160 bytes, 250069680 sectors.

https://www.tenforums.com/tutorials/81502-convert-windows-10-legacy-bios-uefi-without-data-loss-33.html
Convert Windows 10 from Legacy BIOS to UEFI without Data Loss. Using MiniTool Partition Wizard Free, you would want to delete the System Reserved partition. Then Copy the EFI System Partition to the empty space. Then Delete the old EFI System Partition. Would have have EFI System Partition - unallocated space - C: drive - unallocated space.

https://appuals.com/convert-uefi-to-legacy-bios-on-windows-7-8-and-10/
STEP 1: Confirming your BIOS Mode. Press Windows key + R to open up a Run dialog box. Next, type 'msinfo32' inside the text box and hit Enter to open up the System information menu. Accessing the System Information window.

https://answers.microsoft.com/en-us/windows/forum/all/windows-cant-access-uefi-after-converting-to-bios/c9852309-1e35-4b81-95c7-9107a2cea66c
Notably, I have never been able to access the BIOS on this PC using F2, ESC, Delete, or F12, even when the PC was functioning correctly. After changing the BIOS settings and rebooting, my previously installed Windows was gone, the dual operating system was gone, and the option to enter UEFI/Firmware was missing.

https://www.dell.com/support/kbdoc/en-pe/000125291/how-to-restore-the-bios-system-setup-defaults-on-a-dell-product
The BIOS or UEFI interface may vary across different Dell computers. See the images below and match the one on your Dell computer for information about how to reset the BIOS or UEFI to factory default settings. If the image does not match, see the user manual of your Dell computer for product-specific information. Figure 1: BIOS with UEFI support.