Stop wifi connecting to open networks I live in a large city and there are random open wifi networks everywhere that allow my Android to connect to their network but won't give internet access because there is a paywall. This is only apparent when you start a browser on the phone. (And is annoying because working mobile 2G/3G access is suppressed in the mean time)

Is there an (automatic) way to stop my phone connecting to a wifi network unless it's password protected ie when I'm at home or at a friend's house?

EDIT: The networks are often named the same eg "BTOpenZone" (but have different IPs so can't be blocked one at a time). There are a wide variety of providers like BTOpenZone. I'd like to block them all, adding exceptions if I ever find a non-paywall connection.
It shouldn't be connecting to WiFi networks unless you have previously connected to them.

If you go into Settings and view your WiFi networks you should see a list similar to:



The ones that are listed as 'Not in range' are networks you have connected to previously. If these are the open networks that you no longer want to connect to you can click on each one and click the 'Forget' button that appears.

Your phone should not connect to these networks again (unless you tell it to).

EDIT: After your edit it appears like this question will help.