If you are trying to upgrade to Windows 11, install a modern OS, or utilize a hard drive larger than 2TB on Windows 10, you might have encountered the dreaded "Selected disk is of the MBR partition style" error. is a powerful, open-source command-line utility designed to solve this by converting MBR to GPT without losing data.
Look for the latest version, often named gptgen-1.1.zip or gptgen-1.3.zip . download gptgen windows 10
Tip: Using a simple folder name without spaces (like C:\gptgen ) helps avoid command-line errors. Prerequisites Before Converting (Crucial) Do not proceed without performing these steps: If you are trying to upgrade to Windows
All commands below must be run in an elevated command prompt. Step-by-Step: How to Use Gptgen in Windows 10 Tip: Using a simple folder name without spaces
gptgen is a lightweight, command-line application that does not require a traditional installer.
Open Command Prompt as Administrator, type diskpart , then list disk to confirm which disk you are converting.