cannot login after upgrade installed packages

With Yast I upgrade all installed packages.
When starting the computer I cannot login. The login screen keeps coming back.
With Alt+F2 I can login to the console. There is no xorg.conf ?

openSUSE Leap 42.1

Problem is /home/anton/serverauth.1566 does not exist

Are you, by any chance, using an ecryptfs encrypted home directory?

The latest kernel update seems to break ecryptfs (see bug 989084).

You should be able to boot the previous kernel (kernel 4.1.26). I suggest you try that, and see if it gets you back up and running.

Thanks no i am not using encryptfs home directory. I have been sorry that I chose to openSUSE leap 42.1 . My old system 13.2 was the best.

Downgrading kernel did not make a difference still cannot login.
linux-nfs:~ # uname -r

I can login as root
init 3

Made a new user which can login to Plasma 5 all works fine.
Now I wonder what could happen with the default user.
How to fix.

Probably a problem with the plasma config files. Should find in ~/.config also maybe remove plasma stuff from ~/.cache

But that is a guess. May be ownership of ~/.Xauthority fie if you have ever logged into GUI as root

Could not see anything strange in ~/.config removed plasma stuff from ~/.cache
chown anton:users .Xauthority

But I keep getting the login loop.
openSUSE Leap 42.1 should be stable but it is not !
after updating only installed packages the login system got broken.

I have a similar problem in Tumbleweed. Mate, Cinnamon, Gnome and Plasma were installed at the same time, from the same snapshot. But the problem presents only in Cinnamon, and not at every login.

There’s only one user in Cinnamon, autologin is enabled. The “login loop” problem occasionally presents roughly every 8th boot. Instead of booting into DE the login screen presents, entering the user’s passwords doesn’t help, login screen disappears for a moment but then turns back.

I didn’t investigate deeply, as the problem doesn’t present on every boot. But I found a way to force the boot to proceed - by simply pressing Ctrl+Alt+Backspace (X restart). The boot proceeds normally after that and arrives up to DE, even without entering the user’s password.