On the proxy server screen select do not use to disable. Unplug all network devices including the ps3 system.

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My ps3 wont connect to the internet. Check your router manual to connect. Again one wrong digit prevents you from connecting to the network. Now youll need to provide your routers security settings. If however it does find a network you. If the ps3 is connected to a modem using an ethernet cable the wireless function will be turned off. Choose internet connection settings advance settings from the list of network settings select custom then choose proxy server from the list.
If you still cant connect on this device. Internet connection settings vary depending on the network environment and the devices in use. This setting is available only on ps3 systems that are equipped with the wireless lan feature. Wait a few minutes before turning them back on this will refresh. Choose internet connections and select enabled. Turn off or move microwaves fluorescent lighting bluetooth devices cordless phones computer monitors and radios.
Make sure to use the shortest ethernet cable you can no longer than 25 feet. The following procedure describes a typical setup when connecting to the internet wirelessly. If your ps3 has even one letter or digit wrong it wont connect. Use only an ethernet cable compatible with 10base t 100base tx or 1000base t networks. Double check the password you entered when attempting to join the network. You should set up a network in your home as this way the ps3 might be able to detect this and attempt to connect to this network assuming it finds a network.
Test your network test your home network by connecting to the internet on another device. Open the ps3 main menu and select settings network settings. To disable the ps3 proxy server. Select settingsnetwork settings on the xmb and click the x button. Set the method for connecting the system to the internet. Make sure your ethernet cable is securely plugged into the network connector on the playstation console and your internet provider modem.