Disconnect the power supply cable. Note that this is the same as the network cable if
the phone uses Power over Ethernet.
Press and hold the little gear like button while you connect the cable again (i.e. starts the Avaya
B179). Hold the button pressed until the SYSTEM RECOVERY menu is shown on the
display.
Press 1 to select Reset configuration and confirm with OK.
You can press any other button than 1, 2, or 3 to start the phone without resetting.
Upgrade to the latest version of the software when the phone has started and redo the
setup of account and other settings