But, if only the legacy BIOS mode is supported you can't convert MBR to GPT. The challenge is, that it is not possible to change the layout to GPT with windows standard tools if the disk already contains data. But you might need to convert system disk to GPT or MBR without operating system in some cases including: ①Encounter 'The specified disk is not convertible' error during converting the system disk to MBR or GPT via DiskPart.exe tool. This will erase any data stored on the disk.
