Can't connect to web service

I have two situations involving web services:

1) I am running a vb.net app that utilizes web services on a web server. This app is running successfully on several other machines in the office. However, I have a brand new machine running windows 2000 that gives the error: "The underlying connection was closed. Unable to connect to the remote server" when I try to run the app. The machine right next to it can connect without a problem. When I take the url from the config file and paste it in a browser it connects to the web services without a problem. Any ideas?

2) I could formerly connect with a VPN connection to a remote server and with a vb.net app that uses web services connect to that server (and the web services) by changing the url in the config file to the appropriate web services. Recently, the SQL Server and web server (with the web services) were moved to new machines. Now when I VPN in and try to use the vb.net app to connect (after having changed the config file's url) I get the error "The underlying connection was closed. Unable to connect to the remote server". I CAN ping the server while being VPN'd. I am using What's up?