Since the upgrade from to Xubuntu 16.04 from Xubuntu 15.10 on a Lenovo Thinkpad Twist (S230u) with Broadcom wireless card the wlan0 device has disappeared. It is as though the physical device was inexistent. How can it be re-activated ?
During the last step of the upgrade process I clicked NO regarding the question whether I wanted to deactivate UEFI Secure Boot. (I don't know whether this is a useful information).
The system is currently up to date.
sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade
--> finish with 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
ifconfig
--> only lists eth0 and lo.
lspci
--> contains a line "03:00.0 Network controller: Broadcom Corporation BCM43228 802.11a/b/g/n". But there is no mention of "wireless" or the like.
iwconfig
--> mentions eth0, wwan0, lo, each with no wireless extensions. Nothing else.
nmcli -f all device show
--> Same situation. GENERAL.DEVICE entries only for eth0, lo and cdc-wdm3 (which should be the mobile broadband device).
update-manager
--> mentions under Additional drivers : Broadcom Corporation BCM43228 802.11a/b/g/n - Using Broadcom 802.11 Linux STA wireless driver source from bcmwl-kernel-source (proprietary).
I tried the solution suggested by David Foerster. But the re-installation process finishes with an error. The situation remains as it is:
lspci -nn -d 14e4:
sudo apt-get purge bcmwl-kernel-source
sudo apt-get update
sudo apt-get update-pciids
sudo apt-get install bcmwl-kernel-source
The result is:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
bcmwl-kernel-source
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/1 515 kB of archives.
After this operation, 8 013 kB of additional disk space will be used.
Selecting previously unselected package bcmwl-kernel-source.
(Reading database ... 259730 files and directories currently installed.)
Preparing to unpack .../bcmwl-kernel-source_6.30.223.248+bdcom- 0ubuntu8_amd64.deb ...
Unpacking bcmwl-kernel-source (6.30.223.248+bdcom-0ubuntu8) ...
Setting up bcmwl-kernel-source (6.30.223.248+bdcom-0ubuntu8) ...
Loading new bcmwl-6.30.223.248+bdcom DKMS files...
First Installation: checking all kernels...
Building only for 4.4.0-21-generic
Building for architecture x86_64
Building initial module for 4.4.0-21-generic
Done.
wl:
Running module version sanity check.
- Original module
- No original module exists within this kernel
- Installation
- Installing to /lib/modules/4.4.0-21-generic/updates/dkms/
depmod....
DKMS: install completed.
modprobe: ERROR: could not insert 'wl': Required key not available
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools (0.122ubuntu8) ...
update-initramfs: Generating /boot/initrd.img-4.4.0-21-generic
Disabling validation via mokutil as described below didn't help either.
