So heres the case: A friend came over to show off their new MB Pro. They wanted to connect to the internet, but since I don't have a router, I thought I would just share the internet connection through Airport. Having no way to test it before their arrival, I thought nothing about it. So when they did arrive, we immediately tried connecting the MB Pro to the iMac. In their airport menu-bar menu we could see 'Daniel ********'s iMac' We click, and it supposedly connects. A new device called Daniel...iMac appears under Shared in a Finder Window. When I click the Icon and name, it opens (in the same window) a blank list, and a bar at the top with the iMacs name, and a button for connect as... We also see the classic spinning black flower thing at the bottom right corner of the window. We think its connected already and go to open Safari; "could not connect to the internet, blah blah..." So i play around in Network Preferences and in Sharing preferences, and nothing. I even try with their new iPod touch, nothing. But when I hooked up the ethernet cable running from the modem to the iMac into the MB Pro, and set up to share internet, the iPod touch connects :| Does anybody know what I could do to fix the iMac's problem? I'm looking to buy an iPhone and use wifi from the iMac, but if it doesn't work, poop. And please don't recommend getting a router, as there is no real point, since this will be the only computer in the house... Thanks for the help. Edit: After playing around with Firewall, and setting it to Allow all incoming connections. (before it was Allow only essential services) Question though: will I be safe if I leave the all incoming connections on? or should I turn it off?