Microphone isn't recognized

I have a logitech microphone that used to work on vista. Everytime I hooked
it up, vista would give me a pop up asking me how I wanted to use it. I would
choose the microphone option and be done with it. One day I clicked the "Do
not show this message again." box and the pop up stopped coming up. Since
then my microphone won't work.

My system has Sigmatel High Definition CODEC. How do I get that pop up to
come back?