Wi-fi
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The other is a pest. There are several networks nearby, all with locks on. There are also two –BTFON and BTOpenzone. When I put wake my iMac from sleep it has jumped from my own router to the BTFON, and will not then connect to the internet, neither for browsing nor for email. SOmetimes it is a simple matter of clicking on my router in the Airport menu, but sometimes I need to re-start the router and enter the password before I can re-connect. Fortunately this situation won't last for ever as I will be reverting to a wired connection as soon as the office is back to normal. But it would be good to know why this is happening and what can be done to stop it.