Share via

Upgrade from10 to 11 but my install of 10 only allows legacy bios

Cabot Thunem 0 Reputation points
2025-10-22T19:48:23.6233333+00:00

My PC easily meets the needs for 11. However my install of 10 will only boot in legacy. When i switch it to UEFI it just sits there and reboots into the BIOS. How do I change this so I can set the BIOS to UEFI when Windows won't let me do the upgrade until I have reset. It is a classic catch22. My BIOS will do it but then Windows 10 won't boot. Until I can boot into Windows 10 with the BIOS set to UEFI, I cannot upgrade.. I cannot upgrade without resetting. Help.

Windows for home | Windows 10 | Recovery and backup
0 comments

1 answer

Sort by: Most helpful
Most helpful Newest Oldest
  1. Carl-L 1,870 Reputation points Microsoft External Staff Moderator
    2025-10-23T08:45:12.13+00:00

    Hello Cabot Thunem,

    Welcome to Microsoft Q&A forum. It's my pleasure to help you today.

    I understand that you are having struggling with upgrade your Windows to Windows 11 because your Windows 10 won't boot in UEFI. Windows 10 is capable of running both with legacy BIOS and UEFI, so if your Windows 10 won't boot after change the BIOS to UEFI, it could be that your disk partition style is not compatible with UEFI.

    First, you should boot your Windows 10 again using the legacy boot. When you get back to your Windows 10, please follow these steps. While these steps will keep your data, you should back up your files just in case.

    • To check your disk partition style.
      1. Type "Disk Manager" on the search bar and press Enter.
      2. Select your disk (Usually is Disk 0), right-click on it and choose properties.
      3. Go to "Volumes" tab and check the "Partition style"
      4. Only "GPT" partition style is compatible for booting in UEFI, MBR partition won't.
    • Convert your disk from MBR to GPT. (Note: this process is not revertible)
      1. Type "Command Prompt" on the search bar and select "Run as administrator"
      2. Type this command one by one and press Enter after each:
        • mbr2gpt /validate /disk:0 /allowFullOS (check if your computer is eligible for conversion)
        • mbr2gpt /convert /disk:0 /allowFullOS
        • You can replace the number 0 with another number if different.
    • Restart your PC and try to change BIOS type. Disclaimer: Microsoft provides no assurances and/or warranties, implied or otherwise, and is not responsible for the information you receive from the third-party linked sites or any support related to technology. If you are going to modify BIOS Settings, please back up all your personal files first to ensure you do not lose data.

    If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.