A proxy server is required for internet access from a corporate network.

Add the proxy server's URL and IP address to the computer's hosts file under C:\windows\System32\drivers\etc.

Enable the use of a proxy server and enter an address for it under Control Panel > Internet Options > Connections > LAN settings.

Open a command prompt and run ipconfig /release, followed by ipconfig /renew.

Set the proxy server as the default gateway under the computer's network connection IP settings by selecting Manual, then entering the proxy server's IP address under Gateway.