u gota help me out ! i cant install my web cam on a mac os x

aahhh okay im a new webcamer
i bought this Dynex webcam from future shop today, and well at the bak it says it supports mac os x or sumthing aka, its suppose to work, but when i went hom and installed it, after i clicked on it to start, it just shows a blank white square wif the word monitor on it, w/e i asumme its the webcam monitor.. but i realized its not really suppose teo be like that, so i went on ma AMSN to tryapple e it out and c if it'll work, well when i send a invitation, sumthing like apple error code- 9405 .... and others said whewn they accepted the webcam thingy, it wont show anything....
wuts the problem ?? does it mena my web cam doesnt support mac sx
sum of my friends said its cus my fire wall blocked the port so my web cam doesnt work, i havta do sumthing to my router !?!? i have no idea ?!?!!!!!!!
pleaseeee tell me what to doo!!!!!!!
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