|From the Sony website:|
"Stream popular online content wirelessly. The Sony's Blu-ray Disc™ Players are Wireless LAN ready models. Simply connect the Sony's USB Wireless LAN Adapter to the USB port for fast and easy connection to the Internet."
Are you using the Sony USB wireless adapter or something else? The machine is configured for the Sony device and probably lacks the capability of loading drivers for any other type of adapter. If you are using the Sony device and that does not work then call them.
Goin' Fishin' (Some day)