The Internet settings are not correct or you are attempting to connect to an incorrect DNS server or proxy server.
Check your Internet settings by going to Settings > [Network Settings] > [Internet Connection Test] on the XMB™ Menu and performing an Internet Connection Test.
If you are connecting the PS3 system directly to a modem without a router, please check that the PPPoE ID and the password provided by your Internet Service Provider are correct by going to Settings > [Network Settings] > [Internet Connection Settings] > [Custom].
If you are using a router, please check the router’s access indicator to ensure that the modem is connected to the network correctly. You can request the router settings information from your Internet Service Provider or the manufacturer of the router.
Reset the PS3 system’s proxy server and check if the DNS setting is correct. If you are unsure what the DNS setting should be, select [Automatic]. Click here to learn how to configure the PS3 system’s network settings.