Hello fcz. I understand you want to turn on your internal microphone and I will do my best to help you with this. The answer to this question differs based on your operating system. Could you please provide the following information:
1. The computer model number. If you require assistance locating this information, please reference this website: http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&docname=c00033108
2. Your operating system. If you require assistance locating this information, please reference this website: http://windows.microsoft.com/en-CA/windows/which-operating-system
Please respond as soon as possible so I can assist you. I'm only here to help!
Mario