Have you tried this, straight from the manual btw
Reset configuration
If you have forgotten the Admin PIN code, the only way to reset it to default is to do a hardfactory reset. This is the same as the factory reset in the system menu (MENU > SYSTEM >FACTORY RESET). Note:This erases all settings, including account information and contacts!Procedure
1.Disconnect the power supply cable. Note that this is the same as the network cableif the phone uses Power over Ethernet (PoE).
2. Press and hold the MENU button while you connect the cable again (i.e. start theAvaya B179). Hold the button pressed until the SYSTEM RECOVERY menu isshown on the display.You can press any other button than 1, 2, or 3 to start the phone without resetting.
3. Press 1 to select Reset Configuration and confirm your selection by pressingOK.
4. When the phone starts, upgrade to the latest version of the software and re-configure account setup and other settings (see Settings configuration on page 37for more information).
Joe W.
FHandw, ACSS (SME), ACIS (SME)
“This is the end of the world, make sure to buy your T-shirt before it is too late"
Original expression of my daughter