I installed Ubuntu 12.04 LTS on my laptop dell inspiron 1440. Wired connection works fine. But wireless connection does not work. I installed the driver. I can see my home wireless net work and configured with password. but after configuring it, it keep saying wireless network disconnected. I removed wired connection and internet does not work with wireless even though I see my network. This is what I did after going through previous questions.
lspci -nn to check what driver I need. The output is; Broacom Corporation BCM4312 802.11b/g LP-PHY [14e4:4315 (rev 01)
As per recommendation I did this;
sudo apt-get install linux-headers-generic sudo apt-get install --reinstall bcmwl-kernel-source sudo modprobe wl
Assuming the wireless switch is on, your wireless should now be working; check:
rfkill list all
But I still get this message "wireless network disconnected" and wireless connection does not work. I ran software updates to make sure I am current before doing the above.
I spent lot of time on this. Any help is greatly appreciated.