STEP_01
Reinstall OS (Diskpart Method)
Standard formatting leaves trace identifiers. You must nuke the drive partition tables completely before laying down the new OS. Run this from the Windows Installation USB.
cmd.exe - Administrator
1.Boot from Windows Installation USB.
2.At the first language selection screen, press SHIFT + F10 to open Command Prompt.
3.Execute the following commands sequentially:
X:\Sources> diskpart
Microsoft DiskPart version 10.0.19041.3636
DISKPART> list disk
// Identify your main OS drive number (e.g., Disk 0)
DISKPART> select disk 0
DISKPART> clean
DISKPART> convert gpt
DISKPART> exit
X:\Sources> exit
4.Proceed with custom Windows installation on the newly Unallocated Space.