Specifically, he was missing the (formerly known as the Realtek HD Audio Manager). Without it, the computer didn't know how to handle the analog signals correctly, couldn't detect jack plug-ins, and couldn't apply equalizer presets.
What are you currently trying to fix? What version of Windows are you running? realtekhighdefinitionaudio64bitwin7win8win81win10r279exe
Use the "Update Driver" feature in Device Manager and point it to the unzipped folder. Specifically, he was missing the (formerly known as