[DrAwesome]

If your using I.E
launch your browser
goto
Tools/internet options/connections/lan settings/
check/tick proxy server and enter alternative addr & port
click ok and close your browser and then launch it again.

or without launching I.E

click on Start button
goto my computer/control panel/internet options/connections/lan settings/check/tick proxy server and enter alternative addr & port
then launch you I.E browser