Question I can't get windows to boot in Uefi because boot files are on anoter drive!

Luke76bg

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Hello guys, because i bought a 7900xt ( it will be here this monday, i have a 7950x3D,64 gigs of ram, and an rx 590 that luckily it will be retired this monday! ) i wanted to enabled resizable bar to not lose any performance on the table with the new gpu. I discovered that i must have Uefi boot partition to be able to use Resizable bar so i decided to convert my windows drive C (ssd) to gpt using EaseUs partition master and of course it was a big mistake! Because i discovered that i have the boot files on another drive (G). Of course if i enable Uefi in bios, nothing happens and the bios boot to the bios itself, i have to enable again csm ( or called legacy ) to boot windows. I discovered this when i tried to create a disk image for windows just in case something could go wrong with the conversion , and windows backup told me that i have to backup two drives, C and G (where i have stored old movies, tv show, etc). I built this pc last october and i had all the drive from the old pc inside when i have installed windows 10. So i guess this is a standard procedure for windows to put boot files on another drive than the system drive ? However i hope it can be fixed with with diskpart like in this thread :


Screen from disk management

G is where i'm pretty sure windows boot files are (it's in italian, it's the only disc with System in the description)

View: https://imgur.com/t35Gs7Y


The tool to see if you can install Windows 11

View: https://imgur.com/cveYq5s
only windows drive is converted to gpt

Disk management with disc C selected


View: https://imgur.com/1xvgoPQ

I make the system files visible and indeed boot files are on G:

View: https://imgur.com/mfu9Ieo

On the C system drive i have these protected system files
View: https://imgur.com/cDHXyej


All the other drives you can see in the screenshot of disk management are in mbr of course, and i don't know if i have to convert them too!

Please help me! All the passages needed to do this!
 
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boju

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So i guess this is a standard procedure for windows to put boot files on another drive than the system drive ?

It is a habit of Windows to do that if multiple drives are connected during installation. If there's a next time, and if it were me, backup everything you need on a separate drive then disconnect it. Reinstall Windows with bios set to Uefi only which will then enable secure boot itself and be Win11 compatible.
 
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Luke76bg

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It is a habit of Windows to do that if multiple drives are connected during installation. If there's a next time, and if it were me, backup everything you need on a separate drive then disconnect it. Reinstall Windows with bios set to Uefi only which will then enable secure boot itself and be Win11 compatible.


Thank you, but I don't want to reinstall windows, i don't need to install windows 11, i just want to fix it with diskpart like it was possible with the other thread i linked here, but i need a little help with all the steps involved!

I mean this, from the other thread :

"It may be necessary to fix UEFI bootloader after converting OS drive from MBR to GPT.
Do it this way. Execute from elevated command prompt. Regular command prompt will give error on last step.

diskpart
list disk
select disk 1
list partition
select partition x

(select 99MB EFI partition, x=2 or x=3)
assign letter=K
(assign drive letter to EFI system partition, drive letter K must be unused)
exit
bcdboot c:\windows /s K: /f UEFI /v"
 
I don't want to reinstall windows, i don't need to install windows 11, i just want to fix it with diskpart like it was possible with the other thread i linked here
So you have already converted drive containing C: partition to GPT.
Remaining steps are:
  1. Create EFI System partition on Disk 4 (Disk containing C: partition)
  2. Create bootloader on EFI partition.
  3. Boot into BIOS and change boot priority. Change first boot device to Windows Boot Manager on 1TB OS drive.
Execute from elevated command prompt. Regular command prompt will give error on last step.
There should be no errors.
If you get any errors, then stop immediately and show screenshot with command output.

diskpart
list disk
select disk 4
(select 953GB disk containing C: partition)
list partition
select partition X
(select 953GB C: partition, partition number is either 1 or 2, replace X with appropriate number)
shrink desired=500
create partition efi
format fs=fat32 quick
assign letter=Q
(assign a free drive letter, if letter Q: is already used up, then choose a different free drive letter)
exit
bcdboot C:\windows /s Q: /f UEFI

Last message should be "Boot files created successfully".

If everything went without errors, then
boot into BIOS and change boot priority.
Change first boot device to Windows Boot Manager on 1TB OS drive.
 
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Luke76bg

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So you have already converted drive containing C: partition to GPT.
Remaining steps are:
  1. Create EFI System partition on Disk 4 (Disk containing C: partition)
  2. Create bootloader on EFI partition.
  3. Boot into BIOS and change boot priority. Change first boot device to Windows Boot Manager on 1TB OS drive.
Execute from elevated command prompt. Regular command prompt will give error on last step.
There should be no errors.
If you get any errors, then stop immediately and show screenshot with command output.

diskpart
list disk
select disk 4
(select 953GB disk containing C: partition)
list partition
select partition X
(select 953GB C: partition, partition number is either 1 or 2, replace X with appropriate number)
shrink desired=500
create partition efi
format fs=fat32 quick
assign letter=Q
(assign a free drive letter, if letter Q: is already used up, then choose a different free drive letter)
exit
bcdboot C:\windows /s Q: /f UEFI

Last message should be "Boot files created successfully".

If everything went without errors, then
boot into BIOS and change boot priority.
Change first boot device to Windows Boot Manager on 1TB OS drive.


Thank you!!!! It seems to have worked!!! However when i restart windows before the bios usual information it appears for some seconds "Press Del or Esc to enter bios setup" i didn't press anything and then windows started normally. This can't be changed right ? It's a feature of the uefi boot ? However thank you really much, absolutely i didn't know how to do this!
 
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