Question Windows 10 Won't Boot from Cloned Image While BIOS is in UEFI Mode

kevinakerberg

Reputable
Oct 14, 2015
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Hi everyone,
I recently upgraded my laptop (an HP ZBook 15u G3) to a new SSD, and I cloned my old Windows image using Macrium Reflect to restore to the new SSD to avoid reinstalling Windows and all of my programs. However, I can only boot into Windows while in Legacy boot mode, in UEFI I get the HP boot screen, then I just hang on a black screen. Any ideas? Thanks.
 

Colif

Win 11 Master
Moderator
If you can only boot in legacy, it is likely your old drive was formatted as MBR

Can you right click start menu
choose disk management
extend the next window so you can see all the columns in top area
take a screenshot and upload it to an image sharing website and show link here.
 

Colif

Win 11 Master
Moderator
how big is ssd? there is no real benefit to using GPT on small drives, only 2 main advantages that GPT has over MBR

MBR can only have 4 partitions (before using extended partitions) and max hdd size is 2,2tb. it can't see any space above 2.2
GPT can have 128 partitions on 1 drive and max drive size is a silly 18.8 million TB.

I would leave ssd as MBR if you don't need either of those

Also, some HP won't let you install windows in UEFI mode and require you to use CSM/Legacy mode to install windows
 
However, I can only boot into Windows while in Legacy boot mode, in UEFI I get the HP boot screen, then I just hang on a black screen. Any ideas? Thanks.
If your source drive has windows installed in legacy mode (MBR partitioning) and
you want target drive to be bootable in UEFI mode (GPT partitioning),
then bootloader partition has to be created manually. You can't just clone it from old legacy image.

Show us screenshot from Disk Management with both - source and target drives.
 

kevinakerberg

Reputable
Oct 14, 2015
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4,680
Here's a screenshot of disk management. Disk 0 is target and disk 1 is origin.
qYnTGTl.png
 
And what error do you get with MBR2GPT utility?

Anyway - with disk to disk cloning mode you can not convert from mbr to gpt. You'd have to use partition to partition cloning mode.
1. Clean target drive and convert it into GPT partitioning scheme,
diskpart
select disk 0
clean
convert gpt
2. Create EFI system partition manually (size 500MB),
create partition efi size=500
exit
3. Clone windows partition in partition to partition clone mode,

4. Use bcdboot utility to fix EFI bootloader
bcdboot C:\windows /s H:
( C: - windows partition, H: - bootloader partition)​
 
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