Which Cisco UCM configuration is required for SIP MWI integrations?
Enable "Accept presence subscription" on the SIP Trunk Security Profile.
Select "Redirecting Diversion Header Delivery - Outbound" on the SIP trunk.
Enable "Accept unsolicited notification" on the SIP Trunk Security Profile.
Select "Redirecting Diversion Header Delivery - Inbound" on the SIP trunk.
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