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Turn the phone over and look for the two three RJ-45 network jacks on the left side of the phone.
If there are two jacks, one One connects to the NAM and the other provides pass-through network connectivity to your computer. Ignore the jack labeled Aux.
Disconnect the jack on the left, the one with the ethernet symbol above it:
. Leave the cable disconnected for 5 seconds. This is port 2 in the image below:
Plug the cable back in and you’ll see the Cisco logo on the display, indicating the phone is restartarting.
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