Settings : Basic settings : Resetting the device to the factory settings
Resetting the device to the factory settings
A reset returns all the settings to the default settings. Network configuration, VoIP connections, directories, call lists and all the individual settings are deleted or restored to the factory settings.
 
Safeguarding personnel settings from the reset: Saving and restoring settings
*    . . . use  to select  Settings     OK    Reset    OK    confirm prompt with Yes
Resetting using the device keys
*Disconnect the telephone from the mains power supply    press the Control key     holding the key down, reconnect the device with the power supply
 
Resetting the device with the Web configurator Rebooting or resetting the system