I got my new iMac yesterday, now can't connect to the internet. I can connect on the same setup with both my pc and my boyfriend's macbook, but when I try to set up the connection to the iMac, it says the ethernet is connected but no internet connection is present. The automatic settings are detecting the IP address but it won't go any further. I've never needed a password or anything for the connection before, it's always just been plug and play. Aargh! I've searched online for help, and what I've found says select "built in ethernet" but I don't even have that option to choose from.