Browse By

Troubleshooting MWI SIP Cisco Unity Connection

Troubleshooting MWI SIP Cisco Unity Connection

When a SIP Integration is done between CUCM and Unity Connection, MWI sometimes fails to work. I feel SCCP is more easier to troubleshoot when compared to SIP.
SCCP uses MWI Directory Numbers to turn ON  and OFF Message Waiting Indicator. But SIP  does not use MWI Directory Numbers to turn ON and OFF MWI. Unity Connection sends SIP NOTIFY Message to Cisco Unified Communication Manager.

Troubleshooting steps

  • Login to Cisco Unified Communication Manager
  • Go to Device > Trunk > Verify that Unity Connection Trunk configured on CUCM has Inbound CSS  configured. The inbound CSS should have the Partitions of the Directory Numbers configured.
  • Go to System > Security > SIP Trunk Security Profile > Verify the Profile configured/used by the Unity Connection Trunk has the following parameters checked.

Accept out-of-dialog refer
Accept unsolicited notification
Accept replaces header

  • Login to Cisco Unity Connection > Users > Search for the user for whom MWI is not working
  • Go to Edit > Message Waiting Indicators > Reset MWI for the Subscriber/Voicemail Box

Now the MWI Light should be turned ON.


Published by Team UC Collabing

3 thoughts on “Troubleshooting MWI SIP Cisco Unity Connection”

  1. Brandon Svec says:

    Just wanted to say thanks for posting this. It helped me solve this very problem. Apparently the default SIP integration settings do not allow MWI to work..

    1. Administrator
      Administrator says:

      Thank you for your feedback, Brandon!

  2. Max says:

    Respect to you sir.
    You should be writing the Cisco doco…

Leave a Reply

Your email address will not be published. Required fields are marked *


Electrical Engineer CCNA Collaboration CCNA Voice CCNA R&S. I'm Electrical Engineer and I work like Support Engineer for a Telephony Service Provider Company. Before that I had position like Pre-Sale Engineer about small and medium multivendor telephony solutions. I have 5 years of experience working in Telephony Multivendor Projects. I am also 3 years of experience working in Support and implementation about Cisco Collaboration platforms: UCS server, UCM, Cisco Unity, Presence Server, Jabber, Gateway. Support Community is most useful in finding design, implementation and support tricks and shortcuts that greatly help me in my daily activities. If you need to contact me, please you can writte me.


CCNA Routing and Switching
Am a technology enthusiast. I work in network support providing support with implementation, maintaining and precisely troubleshooting the infra.
Realm of collaboration makes me want to learn and face new challenges more and more.