How to Change a GUID Partition Table Disk into a Master Boot Record Disk

As MBR (Master Boot Record) partitioning supports for disks larger than 2 terabytes. MBR disks uses standard BIOS partition table whereas GPT disk uses unified extensible firmware interface (UEFI).

Here is a detailed tutorial to change a GUID Partition Table Disk into a Master Boot Record Disk:

Using the Windows interface:

  1. First and foremost step is to move or back up the data present on the basic GPT disk which is to be converted into a MBR disk.
  2. If there are any partitions or volumes of the disk then first delete that partition or volume by right-clicking on that and select delete volume or partition.Convert MBR into GPT disk in Windows
  3. Now right-click on the MBR disk and click Convert to MBR disk.

Using command line:

    1. Same as using in Windows interface, backup or move data from GPT disk which is to be converted.
    2. Run cmd as Administrator by right-clicking on command prompt and selecting Run as Administrator.
    3. Type diskpart and press Enter.
    4. Type list disk and press Enter. If there are no partition or volumes present on the disk please skip to step 7.
    5. Now type select disk <disknumber>. Here <disknumber> will be the number of that disk which you want to convert.Convert MBR into GPT disk using command line
    6. Type clean. All partition or volumes present on the disk will be cleaned now.
    7. At the DISKPART prompt, type convert mbr. This command will convert an empty basic disk with the GPT partition style into a basic disk with the master boot record (MBR) partition style.

This article applies to the following operating systems:

  • Windows 8
  • Windows Server 2012
  • Windows 7
  • Windows Server 2008
  • Windows Server 2008 R2
  • Windows Vista
  • Windows Server 2003 SP1
  • Windows Server 2003 (64-bit)
  • Windows XP x64 edition