At your Windows 7 Start Menu type this in the Search Bar at the bottom: update device drivers
Choose the Control Panel option named Update Device Drivers
When the Device Manager window opens find the Imaging Device list.
You should see your Webcam option listed there. If not at the top of the Device Manger look at the Action Menu. Choose Scan for hardware changes.
When you see your Webcam device listed right mouse click on the device and choose Update Driver Software.
Use the first choice "search automatically for updated driver software'. Just be sure you're connected to the internet.