Introduction#

MBR2GPT is a Windows tool that allows you to change a disk formatted with the MBR (Master Boot Record) method to GPT (GUID Partition Table) without losing any data. This is commonly used by people transferring complete Windows installs to new drives for use on new computers whose only method of booting operating systems are through UEFI (Unified Extensible Firmware Interface). After cloning a customer’s drive to their new computer’s drive, you will most likely want to use this.

Prerequisites#

  • Windows 10 or 11, older versions YMMV
  • Windows install media that matches the existing OS version (if you’ve got 10 already installed, use that)

Step 1: Getting a command prompt#

  1. Insert a Windows install USB into the computer with the corresponding version loaded onto it. If the cloned drive has Windows 10 on it, use Windows 10 install media. If it has 11, use that.
  2. When you’re at the “Install Windows” splash screen, press Shift+F10 to launch a Command Prompt window.

Step 2: Using diskpart#

  1. At the C:\ prompt, type diskpart. This is Windows’ command line disk partitioning tool.
  2. At the DISKPART> prompt, type list disk to list all disks connected to the computer.
  3. Find the disk with the correct size. Usually there will only be two - your OS drive and the install media - so select the biggest one in this case. Most times it will be disk 0 but you should double-check anyway. Take note of that disk number and exit diskpart by typing exit.

Step 3: Converting the drive#

  1. Back at the C:\ prompt, you’ll want to enter mbr2gpt /validate /disk:X, where X is the disk number we found in the previous step. You should see MBR2GPT: Validation completed successfully. If you do, you may continue to the next step. If not, consult the Troubleshooting section or the internet.
  2. You may now convert the disk to GPT. To do this, type mbr2gpt /convert /disk:X, where X is the same disk number from the two previous steps. If you see MBR2GPT: Converstion completed successfully, you may now reboot by typing wpeutil reboot! Otherwise, consult the Troubleshooting section or the internet.

Troubleshooting#

to do :3