Prevent Mac from connecting to WiFi networks with same name as preferred network How can I prevent OS X (and ideally iOS devices as well) from connecting to a WiFi network which has the same name as one of my preferred networks, but isn't the same network?

For example say my favorite coffee shop has an open WiFi network named "Free WiFi" and that's fine, but so does neighbor who runs a proxy which changes all the images sent over HTTP to pictures of butts… hilarious… but[t] annoying.
Obviously you joined neighbors network once upon a time.

Since you have the "Remember networks this computer has joined" Enabled, it will remember it.

Find it and delete it in networks - advanced, or just delete both and next time reconnect in the coffee shop, but do not connect to Free WiFi if showing up when at home.

The fact that they have the same name showing "Free WiFi" is only for us humans, the computer use BSSID to identify the stations.