Windows 10: Creating boot partitions from scratch

First, boot a Windows 10 or Windows Server 2019 rescue CD and enter the command prompt.

Step 1a: If you have the 128MB + 100MB partitions and they are broken for some reason

diskpart

list disk
select disk
list part
# visually check you are about
# to do the right thing
select part 1
delete part override
select part 2
delete part override

Now continue with step 2.

Step 1b: If you don’t have at least 228MB of unpartitioned space in front of your Windows partition

Boot the gparted Live CD and move your Windows partition to the right, 250MB is usually fine, then continue with step 2.

Step 2: Recreating the UEFI boot partitions and installing the bootloader:

create partition efi size=128
format quick fs=fat32 label="System"
assign letter="k"
create partition msr size=100
exit

bcdboot C:\windows /s k: /f UEFI

Step 3: Profit

That’s all there is to it! Make sure to set your computer to UEFI ONLY, because it’s past 2020.