If your webcam is not recognized by your computer or Microsoft LifeCam, press Windows + R key combination, type devmgmt.msc and click OK. Expand the Universal Serial Bus controllers and Imaging devices lists, right-click on the webcam driver and select Update Driver Software. Use the Browse option to navigate to the installation package, select the driver and install it following the on-screen instructions. This should fix it. If you don't have the installation package for your webcam or if this doesn't solve the problem, I suggest you contact Microsoft. Also, if you want, you can try another webcam capture utility from Software Informer database.