shutdown option gone

[Thomas]

Again me.
When I tried to shutdown the computer to go home, I noticed that there 
is no "shutdown option" any longer.
I believe, it has been there before.

When I click on that "Kickoff" thing and then on "Leave", I get:
1)    Lock out (end session)
2)    Lock (lock screen)
3)    Switch user

That's it.
No restart or shutdown option.
Pressing Crtl-Alt-Delete also offer ONLY
1)    Lock out
2)    Cancel

So, if I want to shut the computer down ... the only choice I have is 
cut the power.
THAT cannot be normal!
(I did that manual update/upgrade thing. It did/does not change anything).

Without me using or changing anything on this computer LOTS of things go 
wrong.
This or similar things have happened a million times already in the past.
With all "flavors" of linux I have tried so far ...

Please! There must be ways/trick to make it run and KEEP running.
I am desperately trying to get away from Microsoft and switch to linus,
but this kind of behavior makes it VERY difficult.

Thank you.
Thomas