how to mend my webcam?

hello everyone, i am using visa home premium the error i am getting is >SetupDLL\Setup.cpp(409)
$7.0.100.1342
@Windows XP Service Pak 2 (2600) IE 6.0.2900.2180
i have tried to uninstall the webcam many times but it's not working, when i open my webcam the windows is black therez nothing coming up, it seems that the webcam is installed because it's not poping up the error message of your cam is not connected so if anybody can help me out in mending my webcam please.
Umar