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Skype for Business 2019 and Cloud Voicemail

Your Skype for Business 2019 Server Upgrade is Ready and your Cloud Voicemail Upgrade awaits!

Microsoft is retiring Unified Messaging (UM) in Exchange Online and replacing it with Cloud Voicemail and Auto Attendant Services. This impacts voicemail processing and Auto Attendant in Exchange Online for all Microsoft customers using these workloads. This means that the processing of voicemails and Auto Attendants that used to happen in Exchange Online, will now happen in Cloud Voicemail which is a part of Skype Online & Teams. Your actual voicemail data will still be stored in your Exchange mailbox.

Microsoft Office 365 Customers will be transitioned to Cloud Voicemail by Microsoft. The Transition timing will vary depending upon how your company has utilized the UM features. Microsoft will notify customers via Office 365 Message Center of their coming transition. The experience for each customer will be transparent- Microsoft will switch your users over to the Cloud Voicemail and perform the necessary validation and testing.

Customers will need to recreate their current Auto Attendants in the Teams Admin Center and switch their phone numbers over to them. This will involve forwarding your number over to a Microsoft service number that can be assigned to a Phone System resource account within Office 365. Directions to add a license to the resource account can be found in the link below. If Cloud Voicemail doesn't yet support the features you need don't worry, you can continue to use Exchange UM for your Auto Attendant until February 2020, we will continue to work with you until that deadline to make sure you are prepared for that deadline.

Currently the Cloud Auto Attendant Does Not Support Transferring to an outside PSTN Telephone Number

Microsoft originally announced on ‎02-08-2019:

Microsoft plans to introduce enhancements to the Cloud Auto Attendant service in Q1-CY2019 to provide customers with the necessary features to migrate their Auto Attendants from Exchange UM online, such as Hybrid Number support, multiple number support, transfer to PSTN, and more.

Microsoft's latest update states this will not be available in time for the retirement of Exchange UM Online.


For more information from Calltower visit this link:



For a listing of the exact feature differences from Exchange UM and Cloud Voicemail check the following link:

For detailed instructions on setting up an auto attendant visit this link:

The End User experience for Cloud Voicemail will change. Users will be able be able to change their preferences from a USP (User Settings Portal). User can access their USP from a hyperlink ( or from the User-Settings Button on their SFB Client. 


There are a few things we need to get out of the way to get you onto this new platform and upgraded to Cloud Voicemail:
  • Cloud Voicemail - Most likely you've seen the notices that Exchange will be expiring February 2020, Cloud Voicemail is available now! Once you move to Skype for Business Server 2019 you'll be automatically upgraded to Cloud voicemail. Since Cloud Voicemail is a part of Skype for Business Online and Teams Online you'll need to enable your Skype Online License in your office 365 Tenant. Just go into your use licensing and flip the switch, and Cloud Voicemail will be available!
  • Skype Online Federation Fix - Once your Skype online license is enabled you may start to experience issues with Federation when communication with users of Skype for Business Online.  We have a work around for this issue that keeps those lines of communications open and allows you to move to Cloud Voicemail with ease.
  • Firewall Updates - If you have a firewall in place and are restricting access certain Skype servers you'll want to re-visit our Firewall Settings page and make sure you have all the latest updates and IP Ranges. We're Adding additional networks and geo-redundancy which requires a lot more IP Address and Ranges. You'll want to make sure your clients are able to communicate with all these new ranges before we upgrade you to Skype for Business 201



Steps to Enable Skype for Business License

Log into O365 Admin Portal and browse to active users:

Select each user select edit for the product licensing section:

Expand the Project Section which contains the users Skype Online license:

Find the Skype for Business Online Toggle:

Toggle the Switch On:

Find the Microsoft Teams Toggle and Toggle it On as well:


Repeat for all Users which need Cloud Voicemail Enabled.

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