strat docky at starup cause shutdown problem

[Mo]

Docky 3.0.0.113
Ubuntu 14.10
Intel HD4000
Unity 7

I installed docky 3 via ppa, it works nicely recently. But yestetday the shutdown choice didn't work. I couldn't confirm which app cause this problem, so I reinstalled system. But the problem still.

Problem: usually click the system menu's shutdown, Ubuntu will give a shutdown confirm dialog. But it become logout immediately.

Cause: I added a startup record in "Startup Application", name:"Docky", command: "docky". Then everytime when I want to shutdown, it didn't works, it immediately logout. I try to remove this record, and start docky manually after boot, the system's shutdown works, the confirm dialog comeback.

p.s. I don't why that I add the startup app cause this problem, and docky3 looks open speed slower than docky2

[Mo (alim0x)]

tried plank, the same problem