My iPad has worked for 9 months on dynamic DHCP, suddenly, today, it stopped working. There was a tick next to the router in WiFi Settings but no wireless icon at the top left of the screen. The other strange thing was that the IP address was 169.xxx.xxx.xxx not 192.xxx.xxx.xxx as it should have been. No other other computers or devices had network problems. The only fix seemed to be to assign a static IP on the router (linked to the iPad MAC address) and the iPad. Can anyone explain what is going on here? I had not made any changes on the router or the iPad by the way.