Your Commands are wrong!
C:\Windows\System32>mbr2gpt /validate /disk:0 /allowFullOS
C:\Windows\System32>mbr2gpt /validate /disk:1 /allowFullOS
copy & paste !
reg query HKLM\SYSTEM\CurrentControlSet\Control /v FirmwareBootDevice
Well I need to spread some rep around first.
But thanks...
@therealsimpsons
There ya go... those commands look right, to me.
And.... they work properly. Mine failed the validation cause my disks are already GPT.
I'm also ON Windows 11 at the moment. I don't know if that matters... probably not.
But I don't think that it is possible to convert the disks that way. A 3rd party tool is needed.
Run
C:\Windows\System32>bcdedit
@therealsimpsons
Translation...
Open a command prompt as admin, and type: bcdedit
Then post a screen shot of the results... you'll have to enlarge the command prompt window to show all the results.
@therealsimpsons
- please- before you (accidentally) destroy your existing installation, take note of the bottom lines in bold in my original post.
As others have said, the EASY way to have Win 10 installed correctly is to remove your existing system disk, put in a new one, disconnect the others, set your BIOS/UEFI to UEFI, and then clean install Win 10.
That way your exisiting installation is safe and you get everything correctly on the one disk. Routine and easy.
There are then ways to get your existing accounts transferred to the new build, should you wish to try that (non-trivial).
Also run the tool I mentioned to check Win 11 upgrade compatibility. If there's some other issue than those we know, you face another hurdle.
Last edited by dalchina; 1 Week Ago at 00:36.
If the System Reserved partition and the Windows partition are not on the same disk.
mbr2gpt /validate /disk:0 /allowFullOS
"Cannot find OS partition(s) for disk 0"
mbr2gpt /validate /disk:1 /allowFullOS
"Disk layout validation failed for disk 1"
C:\Windows\setuperr.log ==> "Wrong boot partition count, expected 1 but found 0"
https://www.youtube.com/watch?v=epckkhxKexQ
Your Diskmanagement Screenshot doesn't allow to give proper advices! Expand columns 1 + 5 so that you can read everything.
Better is to run Command Prompt as admin
C:\Windows\System32>diskpart
sel disk 1
list par
exit
Check your BIOS and find out where you have to switch from Legacy ==> UEFI
That will be needed after the conversion from MBR to GPT. Don't run the above mentioned bcdboot-command!!!!
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