Broadcom BCM4331: "device not ready firmware missing" error

Just installed Ubuntu 12.04 and I can't connect to my wireless network. My network doesn't even appear. I have a message it says:

device not ready firmware missing.

This is what I get when I run, lspci -nn | grep 0280 in terminal:

03:00.0 Network controller [0280]: Broadcom Corporation BCM4331 802.11a/b/g/n [14e4:4331] (rev 02)

Please help me to get this working.

Solution 1:

You need to manually install the b43 driver.

Open Ubuntu Software Centre and search for b43 and click to install it.
Then reboot and the wifi should be working.

Solution 2:

Try running jockey-gtk and see if it offers you to install a proprietary driver for your network card. You will need an Internet connection to install the driver, so connect your PC to your home network with an ethernet cable.

Here is what the jockey-gtk utility looks like, the proprietary driver for your card should be in this list: