I have a problem somewhat similar to the one in this question..
I am on Ubuntu 16.04 LTS and I usually install system updates when they are available. Yesterday I noticed that when I click on shutdown, the computer shows Logout and Lock dialog just before loging out AUTOMATICALLY instead of shutting down. I have to run shutdown command on the terminal to really shut down my computer. The above link did not help me. Hope you can understand me and solve my problem.
qdbus com.canonical.Unity /com/canonical/Unity/Session com.canonical.Unity.Session.Shutdown
Does it log you out or shutdown ? This is supposed to be the same call that gets executed from the session indicator – Sergiy Kolodyazhnyy Jul 21 '16 at 23:50