Brother MFC-3420C - Manual (Page 62)

3 - 5 USING THE BROTHER CONTROL CENTER
Scanner settings for Scan, Copy and PC-Fax buttons
When the Pop-Up screen appears, you can access the Scanner
Settings window.
Click the Smart Click Control Center icon at the top right of
the Brother Control Center screen
—OR—
Click the Modify Settings button on any of the Configuration screens.
Global settings
AutoLoad Pop-Up—Select this checkbox if you want Brother MFL
Control Center to load when you turn on your computer.