Pressing Fn-Esc to activate the Webcam presents the Warning message "Camera is not yet installed!", followed by creation of an "Unknown Device" under the USB controllers. Reading other forums advises that the webcam device driver relies on the USBVideo.sys file provided with XP, but I've found no (helpful) advice anywhere as to how to re-create my USB device (as the original USB video device.
I'm not sure what caused it to disappear - I suspect a recent microsoft update has interfered with the plug-n-play recognition for this device, but this is conjecture. Has anyone seen this symptom &/or can anyone help me recover the webcam device?