First, make sure you follow the instructions from your camera manufacturer to ensure the proper installation of your camera.

This involves inserting the camera installation CD, being guided through a few steps for installation, and restarting your computer. Plugging in the camera's USB cord at the incorrect time during the camera software installation procedure can cause various problems.

To reinstall your webcam:

Uninstall any existing camera installations. Click "Start," "Settings," "Control Panel," and "Add/Remove Programs." From the list, choose your webcam software and click Remove.

Unplug the camera's USB cord from the computer.

Reboot your computer.

Insert your camera's setup/installation CD.

Follow the instructions described by the camera setup program, and plug in your camera only when prompted. This is usually done after restarting your computer.