Monday, 25 May 2009

Exchange 2010 and MWI

For months prior to the Exchange 2010 Beta being released there where rumours going around about what new features would be added.

One of the biggest features that interested me was something as seemingly minor as MWI. It is something that every voicemail system had, something that everyone took for granted, until it was no longer there.

Ever since Exchange 2007 came out, MWI has given me and many other consultants nightmares. The never ending discussions with customers as to if they needed MWI, it going so well until the one group of people (usually the Senior Executives)  that just couldn’t do without it. Everyone else was usually happy when it was pointed out that they lived in outlook so would just see the email.

Then came the painful discussion of, well you could have MWI but it would cost, and usually not a small cost either.

Well now those days are over and once again I can go into a meeting to discuss the advantages of moving to Exchange UM, without spending time talking about MWI (Let’s just hope fax support is not mentioned).

In order to see how good the MWI support is, I decided to set-up a new Exchange 2010 system and connect it to a Cisco CallManager 7. To my amazement MWI just worked, leave a voicemail and MWI lights up.

Who would have thought a small red light could bring so much pleasure (and grief)….


  1. We attempted to set this up however MWI does not come on. We currently use Nortel CallPilot and CM is set to send the phones a 1000 for MWI and a 1001 for MWI off. How does CM translate the SIP notify MWI On message to the digits that the phone is expecting for MWI On and Off?

  2. It does not use the two DNs for switching MWI on or off, it is done through the SIP Messaging.

    I have not looked at this again since the Beta release but since we hit RTM on Monday, I will take another look with the RTM code.

    What CUCM version are you running? I have only tested against 7.X


  3. I'm assuming you also used Cisco 79XX IP Phones to test. Are the phones using the SCCP or SIP firmware from the CUCM 7.x server?


  4. They were 7961's I think with SCCP but I do not have access to the system at the momment to check.

    If you let me know what you are running I will try and replciate next week with the RTM code.


  5. Hi Adam,

    There is a setting in CUCM that needs to be configured to make MWI work for CUCM. Check it out here