Check if Windows 10 is using UEFI or Legacy BIOS  

I use this PowerShell one-liner (found here) to extract the info from the setupact.log:

Code:

if (Test-Path $env:windir\Panther\setupact.log) {(Select-String 'Detected boot environment' -Path "$env:windir\Panther\setupact.log"  -AllMatches).line -replace '.*:\s+'} else {if (Test-Path HKLM:\System\CurrentControlSet\control\SecureBoot\State) {"UEFI"} else {"BIOS"}}

The only downside is that it has to be run elevated.

Hope this helps...

I tried to do the above recommendations and got this error at the end.

Windows Boot Manager--------------------identifier {bootmgr}device partition=C:description Windows Boot Managerlocale en-USinherit {globalsettings}flightsigning Yesdefault {current}resumeobject {d7c4915f-2dc0-11ea-a2f0-e1e74d1cf6d0}displayorder {current}toolsdisplayorder {memdiag}timeout 20Windows Boot Loader-------------------identifier {current}device partition=Cath \WINDOWS\system32\winload.exedescription Windows 10locale en-USinherit {bootloadersettings}recoverysequence {d6515e33-2daf-11ea-8571-9bd0ddeea7ca}displaymessageoverride SystemRestorerecoveryenabled Yesflightsigning Yesallowedinmemorysettings 0x15000075osdevice partition=C:systemroot \WINDOWSresumeobject {d7c4915f-2dc0-11ea-a2f0-e1e74d1cf6d0}nx OptInbootmenupolicy StandardC:\WINDOWS\system32>wpeutil UpdateBootInfo'wpeutil' is not recognized as an internal or external command,operable program or batch file.

In option 3, I suggest adding the following command, which will find only the path, so that users need not look for it

bcdedit | find "path"

Code:

C:\Windows\system32>bcdedit | find "path"
path                    \EFI\Microsoft\Boot\bootmgfw.efi
path                    \Windows\system32\winload.efi

@Brink,
Please look at option 3 again⁠—you typed [C]bcdedit | find "path"[C]
It should be bcdedit | find "path"
A forward slash is missing from your closing tag.

When booting with a WIndows 10 iso it can boot when the computer BIOS settings are:
UEFI without CSM
UEFI with CSM
BIOS / Legacy

Without going into the BIOS is there any command that can be run to see whether the computer is or is not using CSM?