Integrated webcam missing

Hi, I have a sony vaio W series, with XP. The webcam was working fine but I had a few issues with skype, so ended up uninstalling the arcsoft web companion software that came pre-installed. It must also have contained the drivers for the webcam - because the integrated webcam disappeared too.

It has literally gone. In device manager there is no option for imaging devices.

I reinstalled the camera driver from the sony website, I also reinstalled the arcsoft web companion but neither can detect a camera.

With device manager there are 2 unusual objects. The first is under non plug and play devices - just titled 'serial' with a yellow exclamation mark, and the details 'this device is not present, is not working properly, or does not have all its drivers installed. (Code 24)'.
The second is under USB Controllers and is titled 'Unknown' and states 'no drivers installed for this device' - under details it says 'USB\VID_000...' I can't update drivers with the camera driver.

I did a full system recovery to factory settings using the sony vaio recovery utility. I did it twice to be sure. The camera is still not detected, and the 2 unusual devices are still located within device manager.

Has anyone come across this before? It seems mad that uninstalling the arcsoft webcam companion can completely kill off the camera. It should come with a warning!

Any help would be really appreciated, thanks