1

Unplug the phone:

  • If using PoE, unplug the LAN cable.
  • If using the power cube, unplug the power cube.
2

Wait 5 seconds.
3

Press and hold # and plug the phone back in.

When the phone boots up:

  • For Cisco IP Phone 6821 Multiplatform Phones, the lights on the light strip and the line keys light up.

  • For Cisco IP Phone 6841 and 6851 Multiplatform Phones, the lights on the headset button, the speaker button, and the handset flash.

4

Press the 123456789*0# keys in sequence to begin the factory reset process.

  • For Cisco IP Phone 6821 Multiplatform Phones, when you press a key, the lights on the line keys and the light strip flash.

  • For Cisco IP Phone 6841 and 6851 Multiplatform Phones, when you press 1, the handset light and the light on the speaker button turn off.

If you press the buttons out of sequence, the phone powers on normally.


 

Do not power down the phone until it completes the factory reset process and the main screen appears.

Before you begin

You must know if your phone is an original hardware release or if the hardware has been updated and re-released.

1

Unplug the phone:

  • If using PoE, unplug the LAN cable.
  • If using the power cube, unplug the power cube.
2

Wait 5 seconds.
3

Do one of the following actions:

  • Method 1: Press and hold # and plug the phone back in.

  • Method 2: Press and hold 0 and plug the phone back in.

    Only the Cisco IP Phone 8845, 8865, 8841, 8851 and 8861 support the method. And the hardware version of Cisco IP Phone 8841, 8851, and 8861 must be 15 or later.

The phone begins the reboot process. The headset button and the speaker button light up.
4

On earlier hardware versions, the Mute button lights up. Wait for the Mute button to turn off.
5

Do one of the following actions:

  • Method 1: Press 123456789*0# in sequence.

    When you press 1, the lights on the headset button turns off. The light on the Select button flashes when a button is pressed.

    After you press these buttons, the phone goes through the factory reset process.

    If you press the buttons out of sequence, the phone powers on normally.


     

    Do not power down the phone until it completes the factory reset process and the main screen appears.

  • Method 2: Press 369# in sequence.

    For the Cisco IP Phone 8845, 8865, 8841, 8851 and 8861, the phone screen disappears. At the same time, the lights on the Headset, Speaker, and Mute are flashing.

6

If you use the Method 2, unplug and plug in the phone again to reboot it.

After the phone reboots, the main screen appears.