MBR2GPT.EXE converts a disk from the Master Boot Record (MBR) to the GUID Partition Table (GPT) partition style without modifying or deleting data on the disk. The tool runs from a Windows Preinstallation Environment (Windows PE) command prompt, but can also be run from the full Windows operating system (OS) by using the /allowFullOS option. MBR2GPT.EXE is located in the Windows\System32 directory