Re: Dell Inspiron 9400, Broadcom BCM4311
Another application seems to be using the package system at this time. You must close all other package managers before you will be able to install or remove packages.
Then close it and reboot. Now open a terminal ONLY and do:
The only application I have open is the Muon package manager!
And if successful, then:
sudo dpkg --configure -a
sudo apt-get remove --purge bcmwl-kernel-source
sudo apt-get install linux-firmware-nonfree
"Oh, Ubuntu, you are my favorite Linux-based operating system" --Dr. Sheldon Cooper, Ph.D.