Hello,
Please take a look on our article :
How to handle updates without elevation
In order to perform a silent update, you need follow the steps:
-enable the option "Install support service" from "Updater page" of your old project.
-enable "Install updates without elevation" from the update project, "Updates" page, "Update Installer" tab.
-enter "/qn" in the "Command line" field from the update project, "Updates" page, "Update Installer" tab.
You could try this command line for a completely silent update :
Best regards,
Sorin