Question about ACU and Update Agent.

I try to Install client 4.91 with the Update Agent activated,
but when I start the installation (from a .bat file) i get a popup box
with Install/Upgrade button. I want the installation to start without
this popup box.

I'm using an unattended file which I have moved to the admin directory
where the cuagent.ini file is.
I have checked acu.ini, cuagent.ini and the unattended file and all
places I have Yes for installation / accepting installation in all

Where does this popup box come form?