Hi, go to the Start orb then select Devices and Printers.
In the Devices and Printers locate your 7520 and using the mouse right click on it.
A menu will appear with Printer properties listed, click on it.
In the 7520 Printer properties click on Device Settings.
In the Photo Tray select 4x6 or 5x7 and click apply. (sample of my 7510 shown below)
