cannot create EFI system partition. Error: 0x000036B7 when running mbr2gpt.exe Cannot find what this error means

Thanks, I used the free Aomei Partition Assistant,.. This worked.

You can also boot into WinRE and run "mbr2gpt /convert"

Press F8 during boot > repair your computer > Troubleshoot > open CMD prompt > mbr2gpt /convert

*Disclaimer*

When you use mbr2gpt, this will likely add an EFI partition to the right side of the C: drive. This will prevent you from expanding your C: drive unless you use a 3rd party tool to move the EFI partition.

I can share good news!

I shrinked the volume size not only by 200 MB but by 2GB via the "Datenträgerverwaltung".

After this resizing, MBR2GPT worked well...

Hope it helps also further users...

Hi, thanks for this hint. Unfortunately it doesn't work:

C:\WINDOWS\system32>mbr2gpt /convert /allowFullOS

MBR2GPT will now attempt to convert the default book disk.

If conversion is successful the disk can only be booted in GPT mode.

These changes cannot be undone!

MBR2GPT: Attempting to convert disk 1

MBR2GPT: Retrieving layout of disk

MBR2GPT: Validating layout, disk sector size is: 512 bytes

MBR2GPT: Trying to shrink the OS partition

MBR2GPT: Creating the EFI system partition

Cannot create EFI system partition. Error: 0x000036B7

MBR2GPT-undo: Extending back the OS partition

MBR2GPT: Conversion failed

How shall I proceed?

Andreas

Hi David,

mbr2gpt is a good tool, but it does fail a lot, if the disk is unbootable after those commands, then that disk cannot be successfully converted, you will not be able to use mbr2gpt, you will have to clean install Windows onto a a drive with a GPT partition style.