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Exchange Unified Messaging Online (ExchUMO) Retirement is Imminent

Microsoft is scheduled to retire ExchUMO February 28, 2020. All Office 365 tenants not using Cloud Voice Mail (CVM or Cloud Voice Mail) will be migrated. The impact on the users of this change should be minimal. The most notable change will be that CVM does not support Subscriber Access Numbers and the ability to dial into that number to listen to voice mails.

Another big change will be the retirement of ExchUMO Auto Attendants. These should also be migrated to CVM by Friday. Auto Attendant is an admin-driven migration; you will need to re-create the existing ExchUMO auto attendant trees in the Cloud Auto Attendant cloud service.

This will affect all clients who:

  1. Use Auto Attendants in ExchUMO
  2. Use Call Queues in ExchUMO
  3. Provide PSTN numbers and connectivity to those Auto Attendants through their on-premises Lync 2013 or Skype for Business deployments. This includes those using ExchUMO Auto Attendants with Cloud Connector Edition deployments.

Moving the Auto Attendants over to CVM can be problematic. Another potential issue is the connection back to the on-premises deployments for the dial tone. 

  • Clients with Skype for Business (2015 or 2019) on-premises should be in good shape
    • They should verify that they have a Skype for Business hybrid configuration
    • Skype for Business hybrid configuration will allow them to assign on-premises phone numbers to the new Auto Attendants via hybrid voice
  • Clients with Lync 2013 have a bigger problem
    • Hybrid voice requires both a Skype for Business Edge and a Skype for Business Registrar
    • The Registrar must be a Skype for Business Standard Edition Pool or Enterprise Edition pool
    • The Skype for Business components must be added to their topology
      • They will NOT have to migrate their users to Skype for Business, they just need to have the Registrar and the Edge in their topology
      • Once they have the Skype for Business components are deployed, they will have to establish a hybrid configuration with Skype for Business Online
    • Clients using any of the ExchUMO features with a third-party PBX will not be migrated to cloud services because they do not support third-party PBX systems

Clients will also need the following:

  1. Acquire Office 365 Virtual User Phone Edition licenses – amount to be determined on a case by case basis (these are free)
  2. On-premises DIDs for testing the migrated Auto Attendants

See Exchange Unified Messaging Online migration support for more details.

Please contact Enabling Technologies for assistance.


Work with our team of Cloud Computing Consultants who have done this so many times they know all of the “minefields” to prevent missteps.