On 07/18/2012 07:28 PM, Malcolm MacCallum wrote:
> I knew about and used ifup (the device is wlan0). It did not solve the problem.

Wireless can be a bit different.

Are you using NetworkManager? If so, what is the output of nm-tool?
If not, is wpa_supplicant running on boot?
In any case, what is the output of ifconfig and iwconfig?
If everything seems in order, does "iwlist wlan0 scan" show you the 
wireless routers you expect to see?