Network issues can definitely be hard to diagnose.
here are some helpful steps to verify where your problem is.
Check IP address: is it 192.168.x.xx ? or 169.xxx.x.xx
if you have a 169 address its a false connect.
what kind of network do you have? is it a Modem/Router combo? is it a modem connected to a router and then to your Blu ray player.
the Modem/Router combos are the most complicated and you may need to consult your Internet service provider (ISP) for help connecting. ( perhaps a MAC filtering issue?)
if you have a problem with your Modem/router try obtaining a router and connecting it to the modem, you may have the best success with a stand alone router than you will with a combo unit since they are less complicated to use.
if you already are using a stand alone, try temporarily turning off your security and testing it unsecured.
is the firmware updated on your router ( not the S70 but the router) sometimes the latest firmware helps.