Make sure your wireless card is enabled!
Most notebooks with built-in WiFi have the option to disable the WLAN card (or antenna) to save power. Using a button or key combination (e.g. <Fn> + <F1>) enables and disables the WiFi functionality.
Please note that on selected models this functionality requires specific software; this will be pre-installed with the standard Packard Bell software bundle.
wireless hotkey and indicator driver (bottom of page)