Hello,
I’m stumped. For added security, I renamed my network and my guest network to something other than my name. Everything went fine, and my Time Capsule rebooted and connected to the re-named network. I also re-connected the two iPhones in our house to the newly renamed network. However, the old network still shows up in the Network system preferences and appears to be still broadcasting. I even clicked the advanced button and deleted it from the preferred networks. I want to remove the old network entirely from showing up. What do I do?
— Kevin Durr
I've never run into this before. Try this: Go to System Preferences. Then Network. Select Airport and then look for the "Advanced" button. You should see a list of "Preferred Networks" -- try removing the unwanted one from there.
See if that helps.