Windows 10: my windows detect mic but doesnt works

I am running Windows 10 pro on my hp prodesk 600 g1 twr pc and I can not get my microphone to work. When I try to use Cortana she can not hear me and when trying ton use an online video messaging service like Facebook Messenger video calls the app will not allow me to make the call as it says I do not have a microphone. Everything that I have found in regards to this issue advises me to go into the sounds section of my device manager and to click on the microphone and either configure, turn on or uninstall and reinstall. However, there is NO microphone to click on when

:)

 

mic detection problem

i have a laptop with windows 10 installed on it , my mic worked perfectly but suddely something happened and my laptop doesnt detect my mic when i plug it in, i have tried different mic and still doesnt work

 

USB Mic Problems.

The next step is what I suggested originally. Try it in a friend's PC or take it to Best Buy and ask them to try it one of their PC's. Have to confirm the mic is working OK.

 

Win 10 mic not working (Siberia V2 headset (jack, not usb) doesnt detect, even tho i have it plugged in

Hey, I recently upgraded to windows 10 before that I had win 8.1 and the mic worked perfectly with no problems then after upgrading to win 10 my mic stopped working, even tho its plugged in. When I go to Sound and my Microphones, it doesnt detect my microphone,
but the headphones work perfectly, i tried to follow other steps, they didnt work, i tried both jack holes (front and back) but neither of them worked, but when i tried the front one, it said Currently not available, but still nothing, i hope someone can help
me solve my problem, thanks.