Hi if your using XP,
Try ROLL BACK DRIVERS or UNINSTALL DRIVERS in device Manager
Uninstall and Reinstall the device,
START>right click MY COMPUTER>PROPERTIES>HARDWARE>DEVICE MANAGER
Let the list build and find the camera in this list.
Select Logitech CAMERA.
Right Click UNINSTALL.
Let the computer remove the device and REBOOT
When the machine restarts it will auto find and reinstall the device
If it doesnt auto install the device then you will need the drivers for the Camera,
These came with the camera on a disk or can be downloaded from the Manufactuers site.
You will need the Name and Model for the camera drivers.
Lastly I dont think GOOGLEs toolbar would have change the Cameras drivers because you would have to give it permission to do this,Unsure if thats very accurate but you can contact GOOGLE.
and select preferences then Help
Maybe it was your last updates or software install?
I hope this clears up your issues.
If you need more help let me know ,Cheers