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Hi there
I would like to convert an existing Windows 10 installation with MBR table to GPT and not have to re-install Windows.
I tried using NIUBI Partition Editor Professional Edition, converted to GPT, committed the changes but could not boot to Windows, in spite of trying different BIOS/UEFI settings. May be I did not do everything right at this point.
It is good I had a Windowsimagebackup or I would have lost everything.
This GPT business seems to stand in the way of upgrading to Windows 11.
I would very much appreciate your detailed advice to non-profi!
Thank you in advance
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Try the following: Use
mbr2gpt /convert /disk:0
But there is one more thing to take care of. Shrink System Reserved below 1 GB before converting, like 500 MB. At 1020 MB MBR2GPT may consider System Reserved a data partition and not convert it to an EFI System Partition. The drive letter can be removed as well.
Hi there
After removing the the drive letter, my plan was to shrink the reserved partition and to merge the unwanted space with C, so only 3 partitions remain, but somehow that was not possible. So I decided to merge it back and went to give conversion a try.
Fortunately, a few moments later, the conversion with your suggested command mbr2gpt /convert /disk:0 worked right away.
Right now, upgrading to Windows 11.
Many thanks for your help navigating through the seemingly endless hoops! 😁👍
Best regards!
I guess I was too optimistic & reported too early.
During the upgrade process some error came up ... error code 𝑥8007007𝑓 ... trying different suggestions to deal with it. Will report back after successful upgrade (or not).
Preemptively implemented a number of suggested measures to correct error code 𝑥8007007𝑓, like an sfc /scannow + dism restorehealth, free space, using Windows tool (although there was hardly anything) etc, let Windows install all optional drivers, although Lenovo Vantage showed all were up-to-date, etc and right now, the upgrade to Win 11 has just been completed. :)
Many thanks & best regards