Web cam problem

Hi,
I have bought a Toshiba Satellite M200 laptop 2 weeks ago.While using Yahoo messenger,for the first time the camera works fine.If it hangs for some reason,if I close the camera and try to restart,it says "locked by other application".I tried to disable the "Chicon traybar exe" in msconfig-->startup so that the camera assistant software does not start up automatically and restarted my laptop.Now if the camera hangs while chatting,it says "webcam cannot be connected."My OS is Vista home premium.Tried to uninstall drivers by clicking on camera assistant software but on restart,vista automatically did not download latest drivers,though connected to internet.I have again downloaded the latest Chicony webcam driver for vista from Toshiba website and same problem.
Toshiba support centre will not help even if it is within warranty as it is not a hardware issue.
Please help. same webcam problem. in some cases it locked by another apliction,in another case says that the web cam driver has failed.