By Bryce / Last Updated November 6, 2019

When convert MBR to GPT in Windows 10?

Generally speaking, you intend to convert Windows 10 MBR disk into GPT under the three following situations:

1. Make full use of large disk space. MBR supports disk size up to 2TB, to use the capacity beyond 2TB, you can convert MBR into GPT.

2. Great more partitions. MBR disk only supports 4 primary partitions or three primary partitions plus one extended partition. As for GPT disk, it almost has no limitation to the number of partition.

3. Solve the error “Windows cannot be installed to this disk. The selected disk has an MBR partition table. On EFI systems, windows can only be installed to GPT disk…when installing Windows 10.

How to convert MBR into GPT in Windows 10 without data loss?

In fact, we can make Windows 10 MBR to GPT conversion with Windows built-in tool Disk Management or Diskpart. However, both of the two ways will require you to delete all partitions first, which means that you have to bear the loss of data or experience the cumbersome process of data backup, delete and restore.

Thus, here introduce you two ways about how to convert a disk from MRB into GPT without losing data in Windows 10. You can choose one way based on the specific situation.

#1. Convert MBR system disk to GPT in Windows 10 via MBR2GPT

According to Microsoft, MBR2GP.EXE, first known in Windows 10 version 1703, is a built-in utility located in Win\System 32 directory. In Windows 10, MBR2GPT allows you to convert MBR system disk to GPT without deleting data. You can apply MBR2GPT as following steps:

* Confirm that your device supports EFI/UEFI Boot Mode before converting MBR to GPT.

Press “Windows” + “R”< type “cmd”< Type “mbr2gpt /convert /disk 0 /allowfullos”< Press “Enter”. Then, you will get the following screenshot.

MBR2GPT Convert

Tips:

  • MBR2GPT utility is available only in Windows 10 version 1703 or later.

  • If the MBR disk is with BitLocker-encrypted volumes, it is recommended to suspend the protection at first. After conversion, you can delete the existing protectors and recreate them to resume BitLocker.

  • After converting system disk from MBR to GPT, enter BIOS to change Legacy to EFI/UEFI.

#2. Convert MBR system /data disk into GPT via a GUI tool

Normally, Windows 10 MBR2GPT can convert MBR system disk to GPT successfully. However, sometimes, you can meet an error message, such as “disk layout validation failed for disk 0”. If you don’t want to spend time on fixing MBR2GPT error, you can turn to this great conversion tool, AOMEI Partition Assistant Professional. Have a look at its highlights:

✌ It has a modern and user-friendly graphic interface, enabling you to complete MBR disk into GPT conversion in Windows 10 effortlessly within few clicks.
✌ It can allow you to change disk partition style into GPT without losing data not only in Windows 10 but also in Windows 7/8/8.1.
✌ Apart from system MBR disk, you can use it to convert MBR external hard drive to GPT without deleting any partitions.
If you have converted a wrong disk into GPT accidentally, you can use this tool to convert the GPT disk back to MBR.

Now, install and run it on your Windows-based machine and refer to the following steps to start Windows 10 MBR to GPT conversion.

✍ You can download the demo version to have a try at first.

Notice: If your computer is a laptop, make sure that the power supply is sufficient.

Step 1. Right-click the MBR disk that you need to convert to GPT and choose “Convert to GPT Disk”.

Convert System Disk To Gpt

Step 2. Confirm the operation and click “OK”. Then, make sure that your system support EFI/UEFI mode and click “Yes”.

Ok To Gpt System Disk

Step 3. You will turn to the main menu. Check the pending operation and click “Apply” to execute your operation.

Apply To Gpt System Disk

Tips:

  • For converting the partition style of system disk from MBR to GPT, a reboot is required.

  • Before converting MBR system disk into GPT, make sure that the machine support UEFI boot. After converting, to boot successfully from the system disk, you need to enter BIOS to change Legacy to EFI/UEFI.

  • To convert a disk into GPT in Windows Server 2019/2016/2012/2008 without data loss, you can use AOMEI Partition Assistant Server.

How to convert MBR to GPT during Windows 10 installation?

When messages such as “Windows cannot be installed to this disk. The selected disk has an MBR partition table” appear, it is highly recommended to convert disk form MBR to GPT to fit UEFI boot mode. As Windows 10 is unable to boot, you can create a bootable media via AOMEI Partition Assistant and then convert MBR to GPT during Windows 10 installation.

Step 1. Plug in USB or CD/DVD to a working computer running Windows 10, fire up AOMEI Partition Assistant Professional and click “Make Bootable Media” in main interface.

Make Bootable Media

Step 2. In this Window, select the way to make a bootable media according to your device. Then, click “Proceed”.

Choose Usb Drive

Step 3. Click “Finish” when the operation progress is over.

Finish

Step 4. Plug in the bootable device to the computer that you plan to install Windows 10 and boot from the bootable media.

Boot from the Bootable Media

Then, the following steps are as same as the steps to convert Windows 10 MBR to GPT.

PS.: All the data on the device will be formatted; it is suggested to backup your important data on the device.