Proxy settings are used to tell Internet Explorer the network address of an intermediary server (known as a proxy server) that is used between the browser and the Internet on some networks. Changing proxy settings is something you usually only have to do if you are connecting to the Internet through a corporate network. By default, Internet Explorer automatically detects proxy settings. However, you might need to manually set a proxy with information supplied by your network administrator. Here's how:
Open Internet Explorer by clicking the Start button . In the search box, type Internet Explorer, and then, in the list of results, click Internet Explorer.
Click the Tools button, and then click Internet Options.
Click the Connections tab, and then click LAN settings.
Select the Use a proxy server for your LAN check box.
In the Address box, type the address of the proxy server.
In the Port box, type the port number.
If your network requires separate proxy addresses for different services, such as HTTP, HTTPS, or FTP, click the Advanced button, and then type the individual proxy server addresses to use.
When you are finished making changes, click OK until you return to Internet Explorer.
In some corporate environments, network or proxy settings might be pre-set or turned off by the administrator.