Convert GPT disk to MBR disk via diskpart command

1. Input "DiskPart" at the search bar. Type list disk and press enter.

2. Type select disk 1 and press enter. Type detail disk and press enter. This will give you a list of all the volumes on the selected disk. If you do not have any volumes listed, then you can go to step 4.

3. Type select volume 5 and press enter. Type delete volume and press enter. Repeat steps 3 for each volume listed in step 2 until you have deleted all the volumes.
4. Type select disk 1 and press enter. Type convert mbr and press enter.

5. Type exit and press enter.

Tips to convert gpt to mbr with Command Prompt:
1. You must have administrator privilege to do this in Windows.
2. Before you convert a disk, be sure to backup anything on the GPT disk that you want to convert to MBR disk. Converting the disk requires that all partitions and volumes are deleted on the disk first.