Hello vickenp,
I understand you are having issues with your Mic not working in Windows 8.1. I did a Google search and came up with dozens of issues with the same description Windows 8.1 with Skype and MIC not working. I am including one below so you get the idea. If your Mic works every where else, but Skype you should post your issue on the Skype Forums.
Please if your Mic does not work on other programs re-post and I will happy to assist you.
I hope I have provided you with the direction you need to get your issue resolve. Thank you for posting on the HP Forums. Have a great day!