It validates the digital signatures of the drivers to make sure no intruders (malware) are trying to sneak in during the boot process. The Final Handover: Entering the Kernel
Binaries often rely on external libraries (DLLs). The loader finds these, loads them, and resolves the function addresses so the app can interact with the OS. windows loader
While Microsoft rarely prosecutes individual end-users (they target commercial counterfeiters), the legal situation is clear. It validates the digital signatures of the drivers