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3) We need to configure FXS attributes to be able to light up the Neon light in the Phone to make visible that there is a Message WatingWaiting.
IPPBX MWI Enable
How to enable MWI signaling on your PBX will depend on the specific PBX you are using, please refer to you IPPBX documentation. To confirm if your IPPBX is sending the appropriate SIP INFO mesages, you can capture a sip trace and when someone leaves a meesage in an extension Voicemail, a message similar to this should be shown:
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