Many a time, during a Windows 10 installation process, you get errors along the lines of “Windows cannot be installed to this disk. The selected disk has an MBR partition table.” It mostly happens when you try to install the latest version of Windows 10 on your old computer that has an older MBR partition style. Windows 10 now supports the newer GPT (GUID Partition Table) disk partitioning scheme. In fact, the newly-released Windows 11 only supports the GPT partition style. So if you want to convert MBR to GPT disk without data loss on your Windows 10 PC, just follow our detailed tutorial.
This guide is to strictly convert MBR to GPT without any data loss. You no longer have to use Diskpart and erase the whole hard disk to convert the partition table. We will be using an official tool from Microsoft called MBR2GPT for this tutorial. It’s a command-line tool, but the process is straightforward. By the way, you can also use this method to make your Windows 10 PC compatible with Windows 11. So without further ado, let’s dive in.
Requirements
Verification
Change Legacy Mode to UEFI in BIOS Firmware
Convert MBR to GPT Without Data Loss on Windows 10
Requirements
- Your PC must support UEFI to be able to convert MBR to GPT without data loss on Windows 10. If you have an older computer and the BIOS only supports Legacy mode, you can’t utilize this method.
Requirements
- Verification
- Before we begin, you will need to verify some information. Press the “Windows + X” keyboard shortcut and open “Disk Management“.
Verification
- Under “System Summary”, look for “BIOS Mode“. If it’s UEFI, your PC is supported, and you can go ahead with the process to convert MBR to GPT on Windows 10. In case it reads Legacy, you will have to follow this guide to change the firmware mode to UEFI. With that said, I suggest even UEFI users boot into their BIOS to find the correct UEFI menu. You will also have to perform this action after the conversion anyway. This way, you will be certain where to look for the correct settings page, post the conversion.
Change Legacy Mode to UEFI in BIOS Firmware
Restart your Windows 10 computer, and while the computer boots up, press the BIOS key. Every computer has a different BIOS key, and you might need to search for it on the internet.
Once you are in the BIOS, move around the different menus and look for “UEFI” or “Legacy”. The option should be under “Advanced Settings”, “Boot Mode”, or “System Configuration”, depending on your OEM. On some PCs, disabling “Legacy Support” enables UEFI. Just make sure UEFI is not greyed out, and Legacy is disabled.
Once the computer boots up, open System Information again and check the BIOS Mode. It should be showing “UEFI”. Now, you are ready to move to the next step.
Convert MBR to GPT Without Data Loss on Windows 10
Note: Before we proceed ahead, I strongly recommend backing up all your valuable and personal files and folders. While the method is tried and tested, you never know when things can go south, especially while dealing with Windows. So go ahead and make a backup. You can learn how to create a full Windows 10 backup via the linked article.
- On the CMD window, paste the below command and press enter. Here, I’m assuming your disk number is 0. If it is something else, change the disk number accordingly. This command is to validate all the configurations.
If you get the “Validation completed successfully” message, you can proceed ahead. If you get any error, make sure your PC is configured to the correct settings, as I have mentioned above.
- At the end, you will see a message saying, “Before the new system can boot properly, you need to switch the firmware to boot to UEFI mode!” So, restart your computer and boot into the BIOS, and change the firmware mode to UEFI. You can follow the steps detailed in the section above to change the “Legacy mode” to UEFI from BIOS. Keep in mind that your PC won’t boot unless you make this change.
