[SOLVED] PC wont boot after doing mbr2gpt convert using third party software

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should i do anything else now im in to rectiify anything or fix the system files etc?
You should delete 50MB system reserved partition.
That is old bootloader. No longer necessary.

After that you could try converting OS drive to UEFI compatible again with mbr2gpt.
Validate first.
mbr2gpt /validate /disk:0 /allowfullos
If validation is successful, then proceed with conversion.
mbr2gpt /convert /disk:0 /allowfullos
Then boot into BIOS and set first boot device to Windows Boot Manager.
 
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Nov 30, 2022
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You should delete 50MB system reserved partition.
That is old bootloader. No longer necessary.

After that you could try converting OS drive to UEFI compatible again with mbr2gpt.
Validate first.
mbr2gpt /validate /disk:0 /allowfullos
If validation is successful, then proceed with conversion.
mbr2gpt /convert /disk:0 /allowfullos
Then boot into BIOS and set first boot device to Windows Boot Manager.
Should i delete the 50mb partition via command prompt or can i do it in disk management
 
Nov 30, 2022
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30
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You should delete 50MB system reserved partition.
That is old bootloader. No longer necessary.

After that you could try converting OS drive to UEFI compatible again with mbr2gpt.
Validate first.
mbr2gpt /validate /disk:0 /allowfullos
If validation is successful, then proceed with conversion.
mbr2gpt /convert /disk:0 /allowfullos
Then boot into BIOS and set first boot device to Windows Boot Manager.
Ive just deleted the 50mb partition, can i reallocate that 50mb to another partition and if so how do i do it as in disk management i cant seem to add it to any other, and i cant stretch any other partition. When i try the above mbr2gpt command, should i do that when logged into windows or should i enter command prompt by restarting into recovery console?
 
Ive just deleted the 50mb partition, can i reallocate that 50mb to another partition and if so how do i do it as in disk management i cant seem to add it to any other, and i cant stretch any other partition.
No. If you try to rearrange partitions to add those unused 50MB, you have a high chance of messing everything up to point of full reinstall.
Just leave it.
When i try the above mbr2gpt command, should i do that when logged into windows or should i enter command prompt by restarting into recovery console?
With /allowfullOS switch you can run from within windows.
Without /allowfullOS switch you can run it from recovery console only.
 
Reactions: MarkyGee84
Nov 30, 2022
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No. Leave it.

With /allowfullOS switch you can run from within windows.
Without /allowfullOS switch you can run it from recovery console only.
awesome, i just did the mbr2gpt /validate /disk:0 /allowfullos and it came back validation completed successfully so i will now try the convert command
 
Nov 30, 2022
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You should delete 50MB system reserved partition.
That is old bootloader. No longer necessary.

After that you could try converting OS drive to UEFI compatible again with mbr2gpt.
Validate first.
mbr2gpt /validate /disk:0 /allowfullos
If validation is successful, then proceed with conversion.
mbr2gpt /convert /disk:0 /allowfullos
Then boot into BIOS and set first boot device to Windows Boot Manager.
I did the convert and got the following failed to update, is that something i need to do anything about?

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 OS partition
MBR2GPT: Creating the EFI system partition
MBR2GPT: Installing the new boot files
MBR2GPT: Performing the layout conversion
MBR2GPT: Migrating default boot entry
MBR2GPT: Fixing drive letter mapping
MBR2GPT: Conversion completed successfully
Call WinReReapir to repair WinRE
MBR2GPT: Failed to update ReAgent.xml, please try to manually disable and enable WinRE.
MBR2GPT: Before the new system can boot properly you need to switch the firmware to boot to UEFI mode!
 
Nov 30, 2022
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Did you run it from elevated command prompt?

Anyway - recovery environment is not essential.
You can get all the functionality from it just by booting from windows installation media.
yes i did run as administrator, ok no worries, should i re run the convert command or just move straight on to change the first boot device in the BIOS
 
Nov 30, 2022
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Windows 8/10 Features -> Other OS. Save and Reboot.
UEFI options should appear.

If still no UEFI options, then set CSM to disabled.
ok so UEFI didnt appear in first boot after selecting 'other OS' and rebooting, so i have set CSM to disabled and have the options below in BIOS. If you look in the above picture UEFI is selected for 'Storage boot option control' and for 'other PCI devices' is that relevant?

View: https://imgur.com/a/LBWwChD
 
Nov 30, 2022
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Windows 8/10 Features -> Other OS. Save and Reboot.
UEFI options should appear.

If still no UEFI options, then set CSM to disabled.
sorry to bother you but i was just wondering about the above last few posts, as atm im still in BIOS waiting for what do do next, i dont mean to sound inpatient, as im very appreciative for your help
 
should i enable secure boot as that is one of the windows 11 upgrade requirements?
No. Do not touch secure boot just yet.
You have to make it able to boot in UEFI mode first.
See, what options are available at Save& Exit/Boot Override.
Do you see any UEFI options?
Try loading optimized defaults (BIOS/Save&Exit)

It may be necessary to recreate UEFI bootloader.
Boot from windows installation media. And show screenshot.
diskpart
list disk
select disk 0
list partition
list volume
 
Nov 30, 2022
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No. Do not touch secure boot just yet.
You have to make it able to boot in UEFI mode first.
See, what options are available at Save& Exit/Boot Override.
Do you see any UEFI options?
Try loading optimized defaults (BIOS/Save&Exit)

It may be necessary to recreate UEFI bootloader.
Boot from windows installation media. And show screenshot.
diskpart
list disk
select disk 0
list partition
list volume
When looking at 'Save& Exit/Boot Override' it is basically greyed out so wont allow me to select it. Other options are:

Under 'BIOS'

Boot configuration: Bootup Numlock State - ON
Storage Boot Option Control - Set to UEFI (Other choices are 'Do not launch'/'Legacy'/'UEFI')
Other PCI Devices - Set to UEFI (Other choices are 'Do not launch'/'Legacy'/'UEFI')

Under 'Peripherals'

Intel Platform Trust Technology (PPT) - Disabled


Under 'Save & Exit'

Boot Override - Only available option is WDC PC SN730 SDBPNTY-512G-1032
 
Nov 30, 2022
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No. Do not touch secure boot just yet.
You have to make it able to boot in UEFI mode first.
See, what options are available at Save& Exit/Boot Override.
Do you see any UEFI options?
Try loading optimized defaults (BIOS/Save&Exit)

It may be necessary to recreate UEFI bootloader.
Boot from windows installation media. And show screenshot.
diskpart
list disk
select disk 0
list partition
list volume
View: https://imgur.com/a/nPKqVM1
 
Then recreate EFI bootloader.
If you get any errors then stop immediately.
diskpart
list disk
select disk 0
list partition
select partition 4
(select 500MB primary partition - old legacy bootloader)​
delete partition
list partition
select partition 2
(select 100MB System partition)​
delete partition override
create partition efi size=500
format fs=fat32 quick
assign letter=H
exit
bcdboot C:\windows /s H: /f UEFI /v
Last message should be "Boot files created successfully".
Show command output.
 
Nov 30, 2022
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Then recreate EFI bootloader.
If you get any errors then stop immediately.
diskpart
list disk
select disk 0
list partition
select partition 4
(select 500MB primary partition - old legacy bootloader)​
delete partition
list partition
select partition 2
(select 100MB System partition)​
delete partition override
create partition efi size=500
format fs=fat32 quick
assign letter=H
exit
bcdboot C:\windows /s H: /f UEFI /v
Last message should be "Boot files created successfully".
Show command output.
View: https://imgur.com/a/eWHw5X5
 

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