How do i unregister a phone extention for a mitel 5330e

SOURCE: How do you do a factory reset on the Mitel 5220 IP Phone ?

To Restore Factory Default Settings:
1. Press both Up and Down Arrow keys simultaneously while powering up the
phone. NETWORK SETTINGS? appears
2. Press NO until TOOLS & FEATURES appears and then press YES.
3. Press NO until RESTORE DEFAULTS? appears and then press YES.
4. Press CONFIRM. The phone resets with default settings.

SOURCE: mitel 5220 ip phone locked out ICP 10.0.0.135

Locked out generally means the phone is off the hook and there is no live call. Just press the X or cancel key, or pick up and hang up the phone.

SOURCE: mitel 5220 ip phone locked out

Make sure that it is a Dual Mode 5220. If it is you can use it as a SIP extension. It wiill say it on the back of the Mitel phone next to the 5220.
If it is a dual mode phone you can purchase a sip trunk from a provider and then would be able to use the phone.
When you boot up the phone hold the blue super key while the phone boots, hit the no softkey till you get to phone mode. Hit yes it will allow you to change the phone from minet to sip. This should get you started in the right direction.

SOURCE: voice mail password reset without current number mitel 5207 ip ph

What voicemail do you have? Login to admin mailbox or login to phone system if you have Embedded voicemail.

SOURCE: How do you do a

Unplug the power from the phone. Hold down the Down Arrow key, and power it back on while holding the key. You will get an option to default the phone to factory settings.

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