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

Page 3 - Seeking answers? Join the Tom's Hardware community: where nearly two million members share solutions and discuss the latest tech.
Nov 30, 2022
40
0
30
Hi All,

I hope you can help me, so i have a custom built gaming pc i had built when i was at university in 2020 and i will list the specs i remember or can see as i now do not have access to my uni email account where i had the email with the full specs in.

I have:

Windows 10 Home operating system
Gigabyte H310M S2H 2.0 Motherboard
Intel i5 Processor
32GB DDR4 Ram
512GB Western Digital PC SN730 NVMe SSD
Gigabyte GeForce® GTX 1660 OC 6G Graphics Card
500w PSU (I think its 500w or maybe 550w??)

So what i was trying to do was get my PC ready so i could upgrade to Windows 11, and to do that i had to change two main things, with the first being to enable TPM which i did successfully within BIOS by enabling Intel platform trust technology (PPT). After this i needed to do the mbr2gpt convert so as to enable secure boot, which i used available software which claims to be able to do the convert whilst still logged into windows 10. Before attempting the convert i deleted the recovery partition as you cannot do the convert if you have more than 3 separate partitions shown in Disk Management Console. I started the convert but got an error message which i cannot remember what it said but I'm sure it was an exceptional error code with lots of numbers, i know, i know, that's no help whatsoever lol.

I was still logged into windows and still able to use everything as normal until i restarted the PC as It said i needed to restart the pc which is what i did and that's when i got the boot error message 'A disk read error occurred press Ctrl+Alt+Del to restart' after the BIOS selection screen (i.e press F12 to enter bla bla bla).

I looked for a possible solution online which is when i found the below information:

Boot from Windows installation media into command prompt mode.
Execute these and show command output
(upload screenshot to imgur.com and post link)

diskpart
list disk
select disk 0
list partition
list volume


If you have more than one disk, then also list partitions of remaining disks
select disk 1
list partition
select disk 2
list partition


Now when i type that in command prompt using a recovery media usb so i can access Command Prompt i can see the partitions on my SSD however i cant boot into windows. This is a link to pic of my results using the above commands:

View: https://imgur.com/a/DVkUswW



Let me know if you need any further in for etc,

Thanks in advance

Mark
 
Solution
Screenshots below:
Bootloader partition is too small. Only 50MB. Recommended size is 350MB - 500MB.
bcdboot command is failing because of this.
You'll have to create a new bootloader.
Execute following and show screenshot.
If you get any errors, then stop immediately.
diskpart
list disk
select disk 0
list partition
select partition 3
shrink desired=500
create partition primary size=500
format fs=ntfs quick
active
assign letter=H
exit
bcdboot E:\windows /s H: /v
Nov 30, 2022
40
0
30
It has iGPU. Then you're good.

Go into BIOS,
disable CSM,
enable Secure Boot,
load default Secure Boot Keys.

After booting into windows you can check Secure Boot State with msinfo32.
i disabled CSM, then enabled secure boot and i got this message pop up

''Secure boot can be enabled when system in user mode. Repeat operation after enrolling platform key (PK)''
 
Did you check msinfo32 ?
It should show Secure Boot State - On.

msinfo-sb-on.png