Stopping AirPort connection to hpsetup

I am having a problem with AirPort automatically connecting to a Computer-to-Computer network named hpsetup. This network shows up one day and then disappears for a few days only to show up again. When I turn AirPort on it connects to this automatically instead of my SSID. In System Preferences under Network - AirPort I have it set up as By Default Join Preferred Networks and my network list only has my SSID in it. Also, I do not have it checked to automatically add new networks to the list. Under If No Preferred Networks are Found I have it on Ask Before Joining Network. With these settings it seems like this shouldn't be happening. How do I keep my computer from connecting to this so I can connect to my SSID and get online?

FYI - I am running OS 10.4.11 if that makes a difference.