What Is an EFI File?
A file with the EFIfile extensionis an Extensible Firmware Interface file.
Where Is the EFI File in Windows?
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Most of the time, this file is stored on a special EFI systempartition.
This partition is typically hidden and doesn’t have a drive letter.
SeeWhat’s the Difference Between 32-Bit and 64-Bit?for more on this if you’re not sure.
In this case,Dis the letter assigned to my optical drive.
Where Is the File in Other Operating Systems?
Still Can’t Open or Use the File?
This is most likely the case if you’ve simply misread the file extension.
Or maybe your file uses the .EFL file extension and is an Encryptafile file.
It’s instead a system file used in macOS.
FAQ
This file is the Boot Configuration Data (BCD) file for your Windows operating system.
On Windows 11/10, accessAdvanced Startup Options>Troubleshoot>Advanced optionsand run thebootreccommand.
The EFI system partition should be in FAT32File Allocation Table (FAT)file system format.
