How do I load the Excel Add-in automatically at Excel start-up?

When the Excel Add-in is run for the first time, you are prompted to activate the automatic loading at Excel start-up.

To view or change this setting, click "Settings" in the Infront ribbon. Automatic loading is activated when the "load Add-in at Excel startup" option is checked in the "Data Engine" tab.

You can double check if the add-in Effull is checked in the Excel add-ins list (click File > Options > Add-ins, then Go).