How to restore the "System Reserved Partition"/EFI partition/windows boot manager


#1

This is a follow-up to https://www.howtogeek.com/192772/what-is-the-system-reserved-partition-and-can-you-delete-it/

Out of curiosity I deleted that 100 MB partition. Here is how I recovered:
Enter the commandline in a recovery environment (e.g. windows install disk).

diskpart
list disk
select disk # Note: Select the disk where you want to add the EFI System partition.
list partition
create partition efi size=100
format quick fs=fat32
assign letter S # pick any free drive letter
exit

bootrec /scanos # Note: Note the volume letter where the Windows OS is installed, maybe C

bcdboot C:\windows /s S:

This recreates the necessary /EFI/Boot/bootx64.efi and /EFI/WINDOWS files on the efi partition.