If your screen resolution is set to below 1280 x 1024 the “Scan” button is effectively off the bottom of your screen. In the first instance see if your resolution can be increased by right clicking on your “Desktop” and selecting “Properties / Settings”.
If your resolution is already at its highest setting you can minimise the ribbon menus in File Stream as follows:
If you have a later version of File Stream (no RYB triangle) then all you have to do to minimise the ribbon is double click on the Ribbon Menu label e.g. double click on the word “Standard” if you are in the Standard ribbon menu. Double clicking on it again maximizes the Ribbon Menu.