If you have deleted the
System Reserved partition, not the
EFI System partition, then take a look at this post. ->
link
How to create the missing EFI System partition.
The
EFI System partition is required to boot the computer, when you are using the
GPT partition style. The UEFI firmware scan your computer's hard disks for existence of the EFI System partition, then run \efi\boot\bootx64.efi file in the EFI System partition. This partion has to be formatted with FAT32 file system.
- For Advanced Format Generation One (4-KB-per-sector) drives, the minimum size of this partition is 260 MB.
- For earlier 512-byte-per-sector drives, the minimum size of this partition is 100 MB.
View attachment 63079
CONTENTS:
-
Option One: How to create the missing EFI System partition, if you still have the unallocated space available for the EFI System partition and
no other unallocated space on the drive.
-
Option Two: How to create the missing EFI System partition, if you have the unallocated space available for the EFI System partition.
-
Option Three: How to create the missing EFI System partition,
if you do NOT have the unallocated space available for the EFI System partition.
> OPTION ONE <
How to create the missing EFI System partition, if you still have the unallocated space available for the EFI System partition and no other unallocated space on the drive.
- Boot the computer using the
Windows 7/8/8.1 installation media.
- On the first screen, press
SHIFT+F10 to bring up the command prompt.
- Run the following commands at the command prompt.
diskpart
list disk
select disk # Note: Select the disk where you deleted the EFI System partition.
list partition
create partition efi
format quick fs=fat32
list partition
list volume Note: Note the volume letter where the Windows OS is installed.
exit
bcdboot X:\windows Note: Replace "X" with the volume letter of the Windows OS partition.
BCDBoot copies the boot files from the Windows partition to the EFI System partition and creates the BCD store in the same partition.
- Remove the Windows installation media and restart the computer.
View attachment 63090
View attachment 63091
> OPTION TWO <
How to create the missing EFI System partition, if you have the unallocated space available for the EFI System partition.
- Boot the computer using the
Windows 7/8/8.1 installation media.
- On the first screen, press
SHIFT+F10 to bring up the command prompt.
- Run the following commands at the command prompt.
diskpart
list disk
select disk # Note: Select the disk where you want to add the EFI System partition.
list partition
create partition efi size=260
format quick fs=fat32
list partition
list volume Note: Note the volume letter where the Windows OS is installed.
exit
bcdboot X:\windows Note: Replace "X" with the volume letter of the Windows OS partition.
BCDBoot copies the boot files from the Windows partition to the EFI System partition and creates the BCD store in the same partition.
- Remove the Windows installation media and restart the computer.
View attachment 63086
View attachment 63087
> OPTION THREE <
How to create the missing EFI System partition, if you do NOT have the unallocated space available for the EFI System partition.
- Boot the computer using the
Windows 7/8/8.1 installation media.
- On the first screen, press
SHIFT+F10 to bring up the command prompt.
- Run the following commands at the command prompt.
diskpart
list disk
select disk # Note: Select the disk where you want to add the EFI System partition.
list partition
select partition # Note: Select the Windows OS partition or your data partition.
shrink desired=260
create partition efi size=260
format quick fs=fat32
list partition
list volume Note: Note the volume letter where the Windows OS is installed.
exit
bcdboot X:\windows Note: Replace "X" with the volume letter of the Windows OS partition.
BCDBoot copies the boot files from the Windows partition to the EFI System partition and creates the BCD store in the same partition.
- Remove the Windows installation media and restart the computer.
View attachment 63093
View attachment 63094
Other instructions.
- Here is info about
UEFI Boot Mode (installing using the
GPT partition style) and
Legacy BIOS Boot Mode (installing using the
MBR partition style). ->
link
- How to download and clean install
Windows 8.1 if you have an OEM computer with UEFI firmware (BIOS) embedded
Windows 8/8.1 product key. ->
link
How to delete the EFI System partition.
-
Windows 7/8/8.1 does not start, if you delete the EFI System partition.
- If you want to delete the EFI System partition, you must use the
delete partition override command.
- Boot the computer using the
Windows 7/8/8.1 installation media.
- On the first screen, press
SHIFT+F10 to bring up command prompt.
diskpart
list disk
select disk #
list partition
select partition #
Note: Make sure to select the EFI System partition.
delete partition override