Why My Computer No Longer Boots After Converting from MBR to GPT?

When I wanted to format my Windows 7 with Windows 10, it prompted a message saying, 'Windows cannot be installed on this disk. The selected disk has an MBR partition table.' I changed all partitions to GPT. I'm unfamiliar with this issue, and I would appreciate the help.

In response to your question, we will explain why your computer no longer boots after converting from MBR to GPT. GPT and Legacy modes are mutually exclusive choices. In other words, you cannot have GPT partitions but have Legacy BIOS implied. There are two choices: one is to convert the GPT disk to MBR, and another one is to enable the UEFI mode on your computer. This article will give you a full tutorial on the two solutions. Continue to read and learn.

Method 1. Convert GPT disk to MBR

EaseUS Partition Master is a powerful disk conversion tool that can help you convert the disk from GPT to MBR without effort. Moreover, it's safer than Disk Management and Diskpart since EaseUS Partition Master would not delete your partitions.

Follow the easy steps to convert GPT to MBR using EaseUS Partition Master:

After converting, you can check if the system disk successfully becomes GPT.

Related Article: How to Tell If Windows Is GPT or MBR

Method 2. Enable the UEFI boot mode

Since the GPT disk can create more than 2 TB, you can keep the GPT partition style and change the boot mode to UEFI.

Here is how to do so:

Remember to restart the computer to boot from the UEFI boot mode.