How to know if the computer is using EFI/UEFI or BIOS firmware interface

To determine whether your computer system is using BIOS or EFI/UEFI please follow the steps below:

1. Login to Windows.

2. Go to Start ► Computer

3. Navigate to C:\Windows\Panther\setupact.log

 
4. Open setupact.log

5. search for the following string:

'Callback_BootEnvironmentDetect: Detected boot environment:'

It should tell us the boot environment: BIOS or UEFI in the following format:

Code:Callback_BootEnvironmentDetect: Detected boot environment: BIOS

OR

Code:Callback_BootEnvironmentDetect: Detected boot environment: UEFI