Windows 10: Convert Legacy BIOS to UEFI

Discus and support Convert Legacy BIOS to UEFI in Windows 10 Software and Apps to solve the problem; I'm trying to follow the Microsoft article "Convert an existing Windows 10 Installation from Legacy Bios to UEFI".The first step is to boot to WinRE.... Discussion in 'Windows 10 Software and Apps' started by Chris RRRR, Mar 3, 2025.

  1. CHRIS RRRR
    Chris RRRR Win User

    Convert Legacy BIOS to UEFI


    I'm trying to follow the Microsoft article "Convert an existing Windows 10 Installation from Legacy Bios to UEFI".The first step is to boot to WinRE. When I click Troubleshoot>Advanced options I don't have an option for "Command Prompt". My only option is "Startup Settings".I booted using a startup disk and in WinRE I went to Troubleshoot>Advanced options>Command Prompt. I entered "mbr2gpt.exe /validate and it said "Cannot find OS partitions for disk 0" output below.Can anyone suggest what I should do next? Can I convert the disk?Thanks,Chris

    :)
     
    Chris RRRR, Mar 3, 2025
    #1
  2. OZLEGEND
    Ozlegend Win User

    Convert an existing Windows 10 Installation from Legacy BIOS to UEFI

    Convert an existing Windows 10 Installation from Legacy BIOS to UEFI without using 3rd party software.
     
    Ozlegend, Mar 3, 2025
    #2
  3. BON2X060391
    bon2x060391 Win User
    Is there a way to convert my existing installed Windows 10 Legacy bios to UEFI?

    Hi guys, is there a way to convert my OS's Legacy BIOS to UEFI? Reason for this absurdity is I want to dual boot Ubuntu 15 and whenever I disable the EFI setting in my BIOS my usb installer is not detected (obviously). I've searched about it and it leads
    me to this article Converting Windows BIOS installation to UEFI I just want to know if there are other steps before I follow the article. Thanks in advance.

    I wanted to use a VM but my rig can't handle such.
     
    bon2x060391, Mar 3, 2025
    #3
  4. DAC81048
    dac81048 Win User

    Convert Legacy BIOS to UEFI

    Problem Regarding Bios Change from UEFI to Legacy

    I have hp pavilion p045tx with windows 10 pro. I recently install Ubuntu with windows 10 so for that I convert my bios setting from UEFI to Legacy mode for install third party software like wireless Driver and all in Ubuntu.
    But after every restart the bios setting change to default and that is to UEFI mode and that will cause an problem of no OS detect. Every time I have to go to bios setting and enable the legacy mode to start my OS. Can anyone suggest me what to do in this
    case.
     
    dac81048, Mar 3, 2025
    #4
Thema:

Convert Legacy BIOS to UEFI

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