Restarting your D60 Gateway can be done in 2 ways.
Option 1: Using the D60 Router GUI
Once logged into the GUI, use the navigation options on the left to navigate to 'System' ➝ 'Reboot/Reset'.
Option 2: Using the On/Off Button on the Back of the D60
Press and release the on/off button. This will power off the D60. Press and release the button a 2nd time to power it back on.