asp.net application calling a web service

I have a web application which calls a third party web service to return data which is then populated to a gridview.

When I run it locally from the visual studio built in 开发者_如何转开发IIS, it works fine. When I publish to our servers and try to repeat the same action, it times out. I have checked all possibilites...if it is running locally, what happens when it gets published to the server machine.

Is it possible that your production machines may have a more strict firewall configuration that is disallowing outbound connections? Or maybe only allowing connections to whitelisted IPs?