I normally use a USB Headset, which works fine and detects under Playback Devices. When I switched over to a 3.5mm Headset, I can use it just fine as normal headphones but the microphone doesn't detect. I always do Windows Updates and I have the latest drivers installed.
I remember when I first had the laptop and I would plug something into the headphone jack, it would ask what device I plugged in and give me a list of options. I picked headphones and saved it as default. Could that be the issue?