Hello
I set Network method on ifup, the system recognize my wlan card BCM4312 and when I try to start it, I get this :

ifup wlan0
wlan0 name: BCM4312 802.11b/g
wlan0 warning: using NO encryption
RTNETLINK answers: No such file or directory
Starting DHCP4 client on wlan0. .
wlan0 DHCP4 client NOT running
RTNETLINK answers: No such file or directory
Cannot enable interface wlan0.
interface wlan0 is not up

Any advice ?