If you are patching manually (not using a pre-made file):
Before attempting a risky manual patch, Dell provides built-in recovery tools for the Latitude 3420: BIOS Recovery Tool (Ctrl + Esc) Download the latest Dell Latitude 3420 BIOS Dell Support Site Rename the BIOS_IMG.rcv and save it to a FAT32-formatted USB drive. With the laptop off and unplugged, hold Ctrl + Esc , then plug in the power. Recover BIOS from the menu that appears. Master Password Reset dell latitude 3420 bios bin file patched
Replacing a non-functional firmware image with a clean, working version. If you are patching manually (not using a