Cannot access wireless network using Sit...

If you have enabled wireless security on the router, make sure you are typing the correct network key. If you still can't connect, try to disable the wireless security first. If you don't know how to disable it, you may reset the router by presssing the reset button at the back for 30 seconds then unplug the power for another 30 seconds. You might as well disable any firewall on your computer like McAfee, Norton, Zone Alarm and the likes.