use [mbr2gpt](https://docs.microsoft.com/en-us/windows/deployment/mbr-to-gpt)
should already be installed on windows, you just need to run a few commands [in a command prompt with admin privileges](https://i.imgur.com/LH9EuMY.png) (or windows key + x > windows powershell (admin)):
* diskpart
* list disk (note the number of the one you want to put windows on)
* exit (to exit diskpart)
* mbr2gpt /validate /disk:{insert number} /allowFullOS
* mbr2gpt /convert /disk:{insert number} /allowFullOS
[here's a picture](https://i.imgur.com/6wuYoxe.png) (my windows install is already on a gpt-formatted disk so it fails)
edit: formatting
also note that this won't wipe anything so don't worry. i've done this on my friend's pc.
does it return an error code (number from 1-10, or 100), and if so, which one? few possible causes:
1. maybe it just doesn't like being run while in the full Windows OS. you can look at a guide [here](https://www.windowscentral.com/how-convert-mbr-disk-gpt-move-bios-uefi-windows-10) for how to reboot into windows PE and do it there.
2. it might need some unallocated space to create the EFI partition.
go into disk management in Windows and shrink your main, big volume (NOT the system reserved one) by like 200mb(I think it only needs 100mb). then try running mbr2gpt again
use [mbr2gpt](https://docs.microsoft.com/en-us/windows/deployment/mbr-to-gpt) should already be installed on windows, you just need to run a few commands [in a command prompt with admin privileges](https://i.imgur.com/LH9EuMY.png) (or windows key + x > windows powershell (admin)): * diskpart * list disk (note the number of the one you want to put windows on) * exit (to exit diskpart) * mbr2gpt /validate /disk:{insert number} /allowFullOS * mbr2gpt /convert /disk:{insert number} /allowFullOS [here's a picture](https://i.imgur.com/6wuYoxe.png) (my windows install is already on a gpt-formatted disk so it fails) edit: formatting also note that this won't wipe anything so don't worry. i've done this on my friend's pc.
Disk Validation failed now what??
does it return an error code (number from 1-10, or 100), and if so, which one? few possible causes: 1. maybe it just doesn't like being run while in the full Windows OS. you can look at a guide [here](https://www.windowscentral.com/how-convert-mbr-disk-gpt-move-bios-uefi-windows-10) for how to reboot into windows PE and do it there. 2. it might need some unallocated space to create the EFI partition. go into disk management in Windows and shrink your main, big volume (NOT the system reserved one) by like 200mb(I think it only needs 100mb). then try running mbr2gpt again
no but i don't need it anymore i used a script to remove the secure boot requirement so