System no longer sees any network connections

[MDuff]

Kubuntu 16.04 on Lenovo Thinkpad T450s
After a recent update was completed, the system froze and upon re-start it could not find any WiFi network. When connected by cable it could not find a cable connection. When I rebooted to Kubuntu 14.04 everything worked but when I booted back to 16.04 no network connections were visible.

There is no mention of this happening to anyone else that I could find.

Does anyone have any thoughts on this strange behavior?

[vinnywright]

boot to your preveous kernel ,,,,,,,,,to get back network,,,,,then run updates

sudo apt-get update && sudo apt-get dist-upgrade

it happened to me Tuesday .

VINNY

[Oderus]

How can i repair this issue from recovery terminal (using wifi) or from live cd? all of my kernals are effected. I know i just have to update but not sure how to go about it from recovery terminal or livecd.

[MDuff]

boot to your preveous kernel ,,,,,,,,,to get back network,,,,,then run updates

sudo apt-get update && sudo apt-get dist-upgrade

it happened to me Tuesday .

VINNY

Tried going back to first kernel but still no network connections visible, wired or wi-fi.
Got fed up and am now doing a re-install of 16.04 and will see if it happens again.

[Oderus]

I booted from a livecd, mounted my filesystem, and used chmod to execute the command. After doing this, I get the same exact error. Screen shot included.

[Darin Miller]

This issue has an easy fix posted in the bug report (https://bugs.launchpad.net/ubuntu/+s...t/+bug/1569674)

Comment #39Ovidiu-Florin BOGDAN (ovidiu-florin):
sudo apt install libkf5networkmanagerqt6=5.18.0-0ubuntu1

then
killall plasmashell && plasmashell &

Fixed my issue!

[Oderus]

This issue has an easy fix posted in the bug report (https://bugs.launchpad.net/ubuntu/+s...t/+bug/1569674)

Comment #39Ovidiu-Florin BOGDAN (ovidiu-florin):
sudo apt install libkf5networkmanagerqt6=5.18.0-0ubuntu1

then
killall plasmashell && plasmashell &

Fixed my issue!

Darin, thank you very much, this did it for me. Any ideas if this package will be fixed or if theres a way to have update ignore it? Its already trying to reinstall itself xD Glad I ran into you on irc last night or i'd still be stuck!

Edit: I just removed the backports software source and its being ignored.

[Darin Miller]

Oderus,

Both 16.04 plasma-staging with plasma 5.6.3 and 16.10, plasma 5.6.4 are working fine. I suspect the networkmanager issue interim update fell through the cracks. The KDE developers are still moving lots of packages around which is creating havoc for the Kubuntu packing developers.

[siabost]

Thanks Darin/Oderus,

I also had this issue after an update two days ago. The workaround (downgrade) worked for me too. I wonder when it will be safe to do a full update again.

[woodsmoke]

MDuff's problem was the same to which I posted in another thread.
The fix worked but after restart did not get the sam error message but does not work.
required a bunch of autoremove.
A restart was stated as required.
killall did exactly that.
posting on a black screen.
woodsmoke