Windows: Microphone Troubleshooting
If nobody can hear you, your may not be plugged in correctly. Check to see that the microphone and headset jacks are indeed plugged in (all the way!) to the correct ports of your computer. Again, if the jacks and ports aren’t labeled or color-coded, you’ll need to use the process of elimination.
Another possible problem is that the microphone is “muted.” Most headsets have a physical volume control on the wire running from the headset down toward the jack: make sure it’s not turned all the way down.
Finally, Windows may be set to disable your microphone. Check the bottom of your Windows desktop. You should see a Volume icon there: 
Right click on this icon, then left click on Open Volume Control.
Normally you will see the following:
Select Options, then Properties. In the window that pops up, click Recording:
Make sure the Microphone box is checked, then click OK. A new window will pop up; check there to make sure the microphone volume is high enough—at least half way up.
Close the window by clicking on the X in the upper right corner. This guarantees that the microphone is enabled, as far as Windows is concerned.
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