Unable to connect to webserice from IIS

I am trying to access a web service which is hosted by a third party service. I am able to browse through the web service URL. The issue right now is am not able to connect to the webserivce when I try access from IIS(5.1). From the visual studio web server 开发者_C百科I am able to connect and get the results When I try from IIS am getting the following error "No connection could be made because the target machine actively refused it "

Thanks, Nithin