Legacy BIOS to UEFI without converting disk from MBR to GPT

In this video I'm going to show you the steps to convert Windows 10 from Legacy BIOS to UEFI without converting the disk from MBR partition style to GPT.

[Gamingking-wtzg]

for people not understanding some things /s Copies the boot environment files to a partition labeled by volumeLetter and creates a new BCD store on it. As the system partition isn’t labeled, this option is not used in the typical deployment scenarios. The user should use this option when configuring a drive that will be used on another computer i.e. a secondary hard drive, or in case the correct boot partition is not automatically identified. More on the difference of deployment depending on the firmware type can be found in the section regarding the /f option below
/f <firmwareType>
Specifies the firmware type. Valid values are UEFI, BIOS and ALL. Used with the /s flag. The UEFI value copies only the UEFI-compatible boot files and initializes a BCD store on a partition specified by the /s flag making it compatible with UEFI-based systems. The BIOS value does the same for BIOS-based systems. The ALL value installs both the BIOS- and UEFI-compatible versions of the bootloader and also configures each of their BCDs accordingly.

[RingZero]

Great Video. I managed to convert my already running Win10 LTSC from MBR to UEFI using mbr2gpt via WinPE. I did not exactly what you mentioned but it definitely gave me ideas thus avoiding a full re-install. I had the entire install without SRP and I wanted to stay that way, however now I have a 100MB Partition 2 right after my C:\ which is Partition 1. Partition 3 being my DATA partition.
The HP Pavilion laptop originally came with Windows 8.1 with UEFI enabled almost 7 yrs ago, did not attempt to change it until last year when I installed Win 10 LTSC in Legacy mode. Well, now with your ideas and suggestions I reached my goal. Thank you! Please keep these videos coming..All the best.

[Redfoot]

Since this video is already two years old, this comment will probably not help... but I followed the steps given and the boot drive still shows as MBR. However, the BIOS finally let me change from CSM to UEFI, which it would not do before. PC Health Check now says that I can upgrade to Windows 11, while the Windows Update screen says I cannot. Gee, I just love Microsoft.

Also, I had quite a bit of effort to get bcdboot to work properly. He never did explain how he knew to set the source to d:\windows. On mine it was c:\windows. I think that part needs more details.

[MCkaven]

I love you <3 i spent 18 hours trying to solve a grub rescue error to efi corruption to windows recovery blue screen and when i almost lost hope I thought i’d give this video a chance before i format the drive and install everything from the beginning and your video gave me the one small missing piece i needed and it worked! So thank you <3

[bigburd]

Wonderful! Worked a treat after other options failed for me. Installed a new UEFI-only MBoard/CPU (MSI MAG B560M with Intel i5 11th Gen: no legacy boot option!). This would not boot my old MBR based win10 hard drive which had a recovery partition at the end which I could not shrink to work around MBR2GPT error "not enough space at end of partition" error. Found this video and followed your instructions, booting from USB Win 10 built from Rufus, instead of trying to delete the recovery partition. Very pleased!

[aitabs]

Is there a way to deal with the boot list option legacy external devices and uefi? how can you add hdd under uefi boot option after installation?

[keshanweerasinghe]

I tried to install windows but I got " windows can not be installed to this disk. the selected dish has an MBR partition table on EFI system. windows can only installed to GPT disks.
windows cannot be installed to this disk.the disk may fail soon.if other hard disk are available, install windows to another location"

My question is "am I boot again windows to the PEN in GPT partition type and install", Is it working ?

Hi there! So i was following same steps as u did in this video but i got stuck at this command
" bcdboot d:\Windows /s c: /f uefi"
Whenever i run that command, it shows this error
"Failure when attempting to copy boot files.
Any way to fix that???

[Gamingking-wtzg]

1.what is the system reversed partition and how can I get it (ok ik sys reversed is for boot files) but my boot and system files are in c drive but how can I move boot files to another partition just like you and what If I don't have that sys reversed partition do I have to format my c drive? 2.what is D:\windows?

[Omgdaddy]

Mine is dell Vostro 15 3568 it was in legacy when I bought it. I want to change this to uefi I tried many methodss including mbr2gpt i only have disk 0 in the disl management menu please help me change it @itarmy 🙏🙏🙏

[denebe]

Hello,
thank you very much for your video.

I have a small question: after you have made this change, that means that your hdd have the system partition MBR (also no GPT), with a UEFI partition (here is the boot loader), but without secure boot, is it correct ?
With a motherboard, we should configured it with: (1) without secure mode (I think it works only with a hdd GPT), (2) CSM (because of the MBR hdd), (3) mode only uefi, or mode uefi or legacy, but not only legacy. is it correct ?

[spork]

failure when attempting to copy boot files. what does this mean?

[junf]

Will this work if my system and boot partitions are on different drives?

[monunishad]

Plz help me converting my drive mbr to gpt without loosing formatting my drive. I have tried doing it by referring one of your video in which you mentioned mgr2gpt.exe file. But I getting validation error index 2. I don't know what to do. Plz help me

[SevenDeMagnus]

Thanks, will this make me able to boot from a UEFI Windows 11, even though I only have a BIOS and not a UEFI type of BIOS?

God bless.

[altaanc]

You are a genius. This process described by you worked for me after i tried some other processes on You Tube which ended up in failure and i had to reinstall Windows from backup. This was done on a Dell Latitude E7450 which was on MBR partition originally. Thanks again and keep up the good work.

[basutapas]

Excellent video👍 My desktop mother board support only Legacy bios. HDD got damaged. But I got HDD from another desktop pc with Windows 10 loaded and with my data. Bcz of GPT (UEFI) style this HDD not booting. I have to recover my all data from this HDD. My mother board is Biostar G41D3+ which is 64bit operating system. I wonder why this mother board having only Legacy bios support?
Should I select sys reserved of GPT hdd partition (100MB) to convert into Legacy (NTFS) ? what cmd should I use? Kindly help me out please 🙏🙏🙏.

[favoureduwadiae]

On my bios there is no UEFI or Secure boot, I don't know if this will work without those options on the bios, please help

[xStrikerBoss]

My computer is bsod and i cant get past boot. Im in a bootloop and the reason is cause i must convert my hdd mbr to gpt. Is there a way to save any data from my mbr hdd before formatting off boot? I have windows 10 on my usb ready to fresh install but i just wanna know if theres a way to save my stuff without being able to boot fully.

[alufetah]

Can we script diskpart with shrinking the OS partition and creating the efi only on computers with disk 0? Have an issue with win7-10 inplace upgrade where all computers so far I have deployed to get the no room for efi error.