Hello,
Thank you for posting in Q&A forum.
The MBR2GPT tool will only work if the system meets the tool's minimum requirements. Some of the requirements include Windows 10 version 1703 or higher, the computer should have 64-bit architecture, BitLocker encryption should be disabled on the disk, the disk should be currently in the MBR, and there should be enough space not occupied by a partition to store the main GPT and auxiliary GPT.
It is recommended to refer to the following links: Fix MBR2GPT failed errors and issues on Windows 11/10 (thewindowsclub.com)
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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