In this post I’d like to point out the most important aspects of the discontinuation of Exchange Online Unified Messaging (hereinafter: EXO UM, voicemail and auto attendant capabilities). EXO UM is discontinued as announced by Microsoft months ago. Now, Microsoft published an information regarding the planned transition towards Cloud Voicemail. Below a short summary of the announced information by Microsoft:

• EXO UM will be transitioned and migrated to Cloud Voicemail in calendar year 2019 (not later than February 2020)
• Voicemail messages can still be stored on Exchange Online as well as Exchange Server
• You’ll receive a transition notification by Microsoft via Office 365 Admin Center
• You can postpone the transition to Cloud Voicemail via the support panel in the Office 365 Admin Center (however before February 2020)
• EXO UM with Lync Server 2010 will not be supported anymore and will not be transitioned
• EXO UM with Lync Server 2013 will be transitioned to Cloud Voicemail
• EXO UM with Lync Server 2015 will be transitioned to Cloud Voicemail
• EXO UM Auto Attendants must migrated to Cloud Auto Attendant services
• EXO UM Auto Attendants must be re-created on the Cloud Auto Attendant service

Conclusion, opinion and summary

EXO UM will be replaced by Cloud Voicemail. The EXO UM service will be transitioned to Cloud Voicemail based on Azure. To me it seems that it will not be a big difference for your users. They’ll still get voicemail and auto attendant capabilities. It’s more an slight cut over to a different backend for the same features.

However, if you are still on Lync Server 2010 you should consider to upgrade to Skype for Business Server to carry on providing voice mail and attendant services.

In case of many auto attendant services on EXO UM you should prepare and plan to re-create auto attendant services on Cloud Voicemail.

Further Resources

• Retiring EXO UM https://blogs.technet.microsoft.com/exchange/2019/02/08/retiring-unified-messaging-in-exchange-online/
• EXO UM migration support https://docs.microsoft.com/en-us/SkypeForBusiness/plan/exchange-unified-messaging-online-migration-support
• EXO UM https://docs.microsoft.com/en-us/exchange/voice-mail-unified-messaging/voice-mail-unified-messaging
• Cloud Voicemail https://docs.microsoft.com/en-us/skypeforbusiness/hybrid/plan-cloud-voicemail