I also see this for folks who run Windows 10 in a VM. Note: this is ONLY available as part of the Creators Update and/or Windows PE.
MBR2GPT.EXE converts a disk from Master Boot Record (MBR) to GUID Partition Table (GPT) partition style without modifying or deleting data on the disk. The tool is designed to be run from a Windows Preinstallation Environment (Windows PE) command prompt, but can also be run from the full Windows 10 operating system (OS).
You can use MBR2GPT to perform the following: - [Within the Windows PE environment]: Convert any attached MBR-formatted disk to GPT, including the system disk.
[From within the currently running OS]: Convert any attached MBR-formatted disk to GPT, including the system disk.
MBR2GPT is available in Windows 10 version 1703, also known as Windows 10 Creator's Update, and later versions. The tool is available in both the full OS environment and Windows PE.
Read more - click here.