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Hey ! I was trying to activate secure boot on my pc but I ran into multiples issues. First my disk is on "MBR" mode, so I used MBR2GPT, however it return that :
C:\Windows\system32>mbr2gpt /convert /disk:0 /allowFullOS
MBR2GPT will now attempt to convert disk 0.
If conversion is successful the disk can only be booted in GPT mode.
These changes cannot be undone!
MBR2GPT: Attempting to convert disk 0
MBR2GPT: Retrieving layout of disk
MBR2GPT: Validating layout, disk sector size is: 512 bytes
MBR2GPT: Trying to shrink the system partition
MBR2GPT: Trying to shrink the OS partition
Cannot find room for the EFI system partition.
MBR2GPT: Conversion failed
What i did next is shrink my disk 0 with an unalocated 1Go partition like
But I still have the same result when launching the command.
Can anyone help me please ? For info, I have a R5 3600xt and a 4060ti, I'm on Windows 10 pro
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Hi,
My name is Igor, it's a pleasure for me to help others and I'll try to help you. I am merely a fellow user trying to provide insight and information that may be helpful to others.
Could it be that you have four partitions already? MBR-style disk can hold only four partitions. so additional EFI partition cannot be created.
You may copy data from one of partitions to another drive (maybe external) and delete this partition temporarily.
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Try the following: Convert the disk from outside Windows, not making use of the allowFullOS option. MBR2GPT may be able to convert the existing System Reserved partition so no new partition needs to be created in the first place.
Hello,
Could you by chance share a screenshot of your current disk layout in Disk Management?
When you convert to a GPT-style disk from MBR, you must have less than four partitions, otherwise, Windows won't be able to create a new EFI partition to successfully convert from MBR to GPT.
Hope to hear back from you.
