xml rpc not working in windows vista

[eluser]Unknown[/eluser]
Hi i'm newbie and i have some problem with xml rpc. why it doesn't work in windows vista and produce error like this "Did not receive a '200 OK' response from remote server."
But in windows xp this error doesn't occur.

[eluser]Yash[/eluser]
Vista... lots of things don't work. crazy os but I love Look.