itunes doesn´t work :(

Hi,
i have win xp pro installed, and want to use itunes for my new ipod now, but everytime i try to install the prog, at the end, it shows me an alarm message, that said that something is wrong, and that they want to send it to microsoft, this also takes place if I want to start itunes itself. Does anybody can know where the mistake could be?????
Would be great....
thanx
Leonie*