Webcam freezes on video call

Hi...
thats basically my problem. my webcam freezes whenever i do a video call on msn (windows live). i read some info on a logitech cam forum, and it suggested that i downgrad to windows live 8.1. it seemed to work for a while, but today, again the cam started freezing. the other persons cam works fine. i contacted sony about this, and they told me to reinstall sony shared library, the cam driver and the camera capture utility. it didnt work, so they said it must be a problem with MSN, and told me to contact them. firstly, im unable to find out how to contact windows live. please note that i got my OS downgraded to XP. please let me know if there's anyway of resolving this problem?? i finally got my S buttons working after days of trying, so i'd like to avoid reinstalling the shared library and wat not. thanks!

EDIT: i have msn plus installed

 

ok...i opened device manager, uninstalled my webcam, and then scanned for hardware changes to reinstall it automatically. the cam ran for half an hour without freezing, until my partner had to leave..and since it didnt run more than 10min before freezing prior to this, i feel its fixed!

 

ok, i was mistaken....its started freezing again..and i have no idea wat the problem is anymore! its really frustrating,pleeease someone help me!

EDIT: i did the above process of uninstalling the hardware and reinstalling it, and it seems to work again...but i fear its only a matter of time before it freezes again, and i cant be doing it all the time!