MBR2GPT Disk layout validation failed

I am trying to convert the OS disk on my server from CSM to UEFI but it fails. The reason I want to do it is because I need to enable resize bar support on there to allocate more RAM for the APU to use. And to do that the disk has to be in UEFI mode. When I enable resize bar the boot mode is instantly changed to UEFI which makes it unbootable. So that's my dilemma.

I have the log for MBR2GPT and I think the error why it failed is:

MBR2GPT: Validating layout, disk sector size is: 512 bytes
2025-02-23 17:07:20, Error                        ValidateLayout: Unexpected partition style, expected 0, found 1
2025-02-23 17:07:20, Error                        Disk layout validation failed for disk 5
2025-02-23 17:07:20, Info                         MBR2GPT: Partition information at error point
2025-02-23 17:07:20, Info                         ===========================================================
2025-02-23 17:07:20, Info                         Partition layout for disk: 5
2025-02-23 17:07:20, Info                         Partition style          : GPT
2025-02-23 17:07:20, Info                         Number of partitions     : 5

I don't know why its numbered as disk 5. Windows is on an M.2 NVME which is the main drive. How it assigned it 5 is beyond me. I'm beginning to suspect that disk 5 is one of the other drives in the system, not the OS drive. How do I find out what number its been assigned?

I want to post the rest of the log here but I can because we can't attach files...

I looked at the file directly under setupact.log, setuperr.log and it contains:

2025-02-23 17:07:20, Error                        ValidateLayout: Unexpected partition style, expected 0, found 1
2025-02-23 17:07:20, Error                        Disk layout validation failed for disk 5

So what can I do to convert the OS drive to UEFI? I am stuck and don't know how to progress further.

These are the specs of my server:

Windows 10 Pro 64-bit

AMD Ryzen 3 2200G Raven Ridge 14nm Technology

16.0GB Dual-Channel DDR4 @ 1594MHz (16-18-18-36)

MSI B450M-A PRO MAX II (MS-7C52) (AM4)

W2261 (1920x1080@60Hz) 2048MB ATI AMD Radeon Vega 8 Graphics (ATI)


931GB Western Digital WDC WD1002FAEX-00Z3A0 (SATA)


931GB Western Digital WDC WD1002FAEX-00Y9A0 (SATA)

931GB Western Digital WDC WD10EADS-00M280 (SATA)


3726GB Seagate ST4000DM004-2CV104 (SATA)

Seagate IronWolf 10TB (ST10000VN000) (SATA)

Kingston 128GB M.2 PCIe NVMe 2580 SSD

AMD High Definition Audio Device