Hai iam madhu.. i have qhmpl 500 lm web cam, i got

hai iam madhu.. i have qhmpl 500 lm web cam, i got free drivers from qhmpl.com, drivers installed in my system but not connecting 2 the cam capturing. i removed that drivers from add/remove programme again installed that drivers but not connecting. ehat is the problem...? ang one more that same cam instlalled 2 other system that system connecting that cam but not connecting ti yahoo messenger... can u please give d answer tomy prob.. please as soon as possible...