BIOS Mode - See if Windows Boot in UEFI or Legacy Mode

How to Check if Windows is Booted in UEFI or Legacy BIOS Mode​

   Information

When the PC starts, the firmware interface controls the booting process of the PC, and then passes control to Windows or another operating system.

UEFI is a replacement for the older BIOS firmware interface and the Extensible Firmware Interface (EFI) 1.10 specifications.

For more information, see:

• Boot and UEFI | Microsoft Docs
• UEFI in Windows | Microsoft Docs

This tutorial will show you how to see if your Windows is booted in UEFI or legacy BIOS (CSM) mode in Windows 7, Windows 8, and Windows 8.1.

OPTION ONE

Check if UEFI or Legacy in Disk Mangement in Windows 7, 8, and 8.1

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1. Do step 2 or 3 below.​

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2. In Windows 8 and 8.1, open the WIN+X Power Users menu, click/tap on Disk Management, and go to step 4 below.​

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3. Press the :winkey: + R keys to open the Run dialog, type diskmgmt.msc, click/tap on OK, and go to step 4 below.​

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4. If prompted by UAC, then click/tap on Yes.​

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5. If your Windows disk shows having an EFI partition like below, then it's installed with UEFI. If not, then it's Legacy BIOS.​

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OPTION TWO

Check if UEFI or Legacy in System Information in Windows 8 and 8.1

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1. Press the :winkey: + R keys to open the Run dialog, type msinfo32, and press Enter.​

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2. In the right pane of System Summary in System Information, see if the BIOS Mode value says Legacy or UEFI. (see screenshots below)​

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OPTION THREE

Check if UEFI or Legacy in setupact.log in Windows 7, 8, and 8.1

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1. In Windows Explorer (Windows 7) or File Explorer (Windows 8/8.1) navigate to the location below and open the setupact.log file.​

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C:\Windows\Panther​

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2. With the setupact.log file opened in Notepad, click on Edit (Menu bar) and Find, or press the Ctrl+F keys.​

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3. Type in this below, and click/tap on Find Next or press Enter. (see screenshot below)​

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Detected boot environment​

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4. Close the Find dialog.​

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5. You will see it say EFI (UEFI) or BIOS (Legacy BIOS).​

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Callback_BootEnvironmentDetect: Detected boot environment: BIOS​

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Callback_BootEnvironmentDetect: Detected boot environment: EFI​

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OPTION FOUR

Check if UEFI or Legacy in WinPE for Windows 8 and 8.1

NOTE: This option can be useful if you are unable to boot into Windows or in WinPE.

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1. Open a command prompt at boot.​

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2. In the command prompt at boot, type the command below and press Enter. (see screenshot below)​

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wpeutil UpdateBootInfo​

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3. In the command prompt at boot, type the command below and press Enter.​

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reg query HKLM\System\CurrentControlSet\Control /v PEFirmwareType​

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4. This command returns 0x1 if the PC boots in Legacy BIOS mode, or 0x2 if the PC boots in UEFI mode.​

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That's it,
Shawn

Related Tutorials

---

• How to See if Hyper-V Virtual Machine is Generation 1 or Generation 2
• How to Check if Secure Boot is Enabled or Disabled in Windows 8 and 8.1
• How to Enable or Disable Secure Boot in UEFI
• How to Boot to UEFI Firmware Settings from inside Windows 8
• How to Install Windows 8 Using "Unified Extensible Firmware Interface" (UEFI)
• How to Install Windows 7 Using "Unified Extensible Firmware Interface" (UEFI)

 

[pennybills]

I tried all methods but failed to find out the boot mode.

I tried looking for the log file in Windows/Panther but there is no file to search the "Detected boot environment"

I also looked in System Information but there is no category that says 'Bios Mode'.


Also tried method 3 even though I don't have Windows 8/8.1 and still doesn't work.

 

[Brink]

Hello Penny,

Are you saying that you do not have a "C:\Windows\Panther\setupact.log" file?

How about with Option One?

What brand and model number is your PC or motherboard?

 

[pennybills]

Hello Penny,

Are you saying that you do not have a "C:\Windows\Panther\setupact.log" file?

How about with Option One?

What brand and model number is your PC or motherboard?

Yeah, I don't have the setupact.log file in that directory.

I tried option 1 but there is no Bios type category.


My laptop is HP Pavilion g6 Notebook PC.

The BIOS Version is Hewlett-Packard F.34 8/16/2011
SMBIOS Version: 2.7
Boot Device: /Device/HarddiskVolume1

 

[pennybills]

I found my problem, there was something wrong with the UAC.

Anyways, looking at my mine attachment, I guess I have Legacy mode right?

 

[Brink]

Yep, that's correct. You're Windows 7 has been installed in legacy and not UEFI.

That's typically how OEMs install Windows 7 though.

Do you know the full model number of your HP Pavilion G6? It looks like some models may not support UEFI.

HP Pavilion g6 Notebook PC series

 

[pennybills]

Yep, that's correct. You're Windows 7 has been installed in legacy and not UEFI.

That's typically how OEMs install Windows 7 though.

Do you know the full model number of your HP Pavilion G6? It looks like some models may not support UEFI.

HP Pavilion g6 Notebook PC series

It's a HP Pavilion g6-1b60us.

HP Pavilion g6-1b60us Notebook PC | HP® Support

 

[Brink]

Penny,

Looking through your manual and drivers at the HP site, I only see mention of BIOS and no UEFI. It appears that you model may not support UEFI installations.

 

[pennybills]

Penny,

Looking through your manual and drivers at the HP site, I only see mention of BIOS and no UEFI. It appears that you model may not support UEFI installations.

So does this mean I can't use Rufus to install Windows 8.1 on my flashdrive?

 

[Brink]

You could still use Rufus to create a Windows 8.1 installation USB flash drive, but you would need to do so without using the GPT for UEFI option, you would use MBR for BIOS.

...or you could use this below instead.

http://www.eightforums.com/tutorials/2227-create-bootable-usb-dvd-windows-8-iso.html

 

[Alamir101]

So I'm on a Windows 8 laptop, now if my computer is UEFI, is there anyway to switch it to Legacy?

 

[Brink]

Hello Alamir, and welcome to Eight Forums.

Yes, but you would have to reinstall Windows 8 to do so.

http://www.eightforums.com/tutorials/2299-clean-install-windows-8-a.html

http://www.eightforums.com/tutorials/13375-clean-install-windows-8-upgrade.html

 

[Alamir101]

Hello Alamir, and welcome to Eight Forums.

Yes, but you would have to reinstall Windows 8 to do so.

http://www.eightforums.com/tutorials/2299-clean-install-windows-8-a.html

http://www.eightforums.com/tutorials/13375-clean-install-windows-8-upgrade.html

Ok, so how would I switch it by reinstalling? I am still not very sure.... I know I need to reinstall Windows 8, but other than that, I'm clueless about what I need to do to change it....

 

[Brink]

Please go ahead and create a new thread for this issue since it will be detailed and go off topic from this tutorial.

 

[Alamir101]

http://www.eightforums.com/general-support/34259-switching-windows-8-uefi-legacy.html#post299244

 

[pennybills]

You could still use Rufus to create a Windows 8.1 installation USB flash drive, but you would need to do so without using the GPT for UEFI option, you would use MBR for BIOS.

...or you could use this below instead.

http://www.eightforums.com/tutorials/2227-create-bootable-usb-dvd-windows-8-iso.html

I tried installing the ISO file on my 4gb file using Rufus and Windows7 Tool but both failed. The iso file is 3.63 and 3.8 on disk and my flash drive only has 3.74.

So.. I put the iso on my old iPod and was able to successfully use the Windows 7 tool to get the iso.

So if I boot my iPod as a flashdrive which was able to successfully have its iso contents on it, I would be able to install W8.1 right?

 

[Brink]

Penny,

I've never tried booting from an iPod, but if you are able to, then you should be able to.

If not, then it may be time to get a larger USB flash drive.

 

[pennybills]

Ahh.. I see.

Thing is I have like 5 different flash drives and they are all 4gb. Buying a new one seems pointless.

Thanks anyway. If the iPod works, then it works but if it doesn't, I'll borrow a flashdrive somehow I guess.

Thank you for all your help and the tutorials.

 

[Brink]

You're welcome. Please let us know how it went.

 

[PrplHaz4]

I'm seeing inconsistent results when checking (on a clean windows 8.1 install)
Option 1: No EFI partition on boot disk (I actually have two bootable drives - the other has an EFI partition, but I don't boot to it)
Option 2: BIOS Mode: UEFI
Option 3: Detected boot environment: EFI

Any idea what would be causing this, or does the article need to be udpated? I'm wondering if I remove the 2nd bootable drive (which I plan to do), will it start reporting Legacy boot? For boot selection, I get what seems to be the UEFI boot screen (with mouse support...etc).