Like a firewall, a proxy server is a kind of buffer between your computer and the Internet. If your computer uses a proxy server connection, and you want to use Windows Messenger features such as file transfer and application sharing, your network and your proxy server must be set up in a way that allows your network or computer to connect directly to the .NET Messenger Service servers. See Related Topics for specific information.

To set up Windows Messenger to use a proxy server:

1. In Windows Messenger, on the Tools menu, and then click Options.
2. Click the Connections tab, and select the I use a proxy server check box.
3. In the Type list, select the type of proxy server your network uses.
4. In the remaining text boxes, fill in the appropriate connection information, and then click OK.

~ Talk to your network administrator to get your proxy server information.

If no proxy server is specified in Connections, Windows Messenger will first attempt to connect directly so that you can use all Messenger features. If Windows Messenger cannot connect directly, it will use the same Hypertext Transfer Protocol (HTTP) connection, including proxy server settings, that your default browser uses to connect to the Internet.

Important: If Windows Messenger uses your browser connection, you'll be able to send instant messages, but some features of Windows Messenger—such as calling a computer or sending files—might not be available.

Notes

~ To see what kind of proxy server connection Messenger is using, click the Tools menu, click Options, and then click the Connection tab. In the bottom half of the dialog box, look for text that describes the connection -- either the default browser's HTTP proxy server settings, or a direct connection (no proxy server).
~ If Windows Messenger connects using a proxy server, features that require two computers to connect to each other might not work with a contact located outside the proxy. Windows Messenger features that require two computers to connect include file transfer, voice and video, Application Sharing, and Whiteboard.