Enable users for Phone System with on-premises PSTN connectivity in Skype for Business Server
This topic describes how to enable users for Phone System with on-premises PSTN connectivity. Before following the steps in this topic, you should read the following: .
To learn how to set up hybrid connectivity, see Plan hybrid connectivity between Skype for Business Server and Skype for Business Online and Deploy hybrid connectivity between Skype for Business Server and Skype for Business Online.
To learn about planning your deployment, see Plan Phone System with on-premises PSTN connectivity in Skype for Business Server.
To learn more about Phone System, including licensing and plans, see PSTN Calling plans for Skype for Business.
Important
Skype for Business Online was retired on July 31, 2021 and PSTN connectivity between your on-premises environment, whether through Skype for Business Server or Cloud Connector Edition and Skype for Business Online, is no longer supported. Learn how to connect your on-premises telephony network to Teams using Direct Routing.
Moving users to Phone System with on-premises PSTN connectivity
Before moving your users to Skype for Business Online, it is recommended that you enable your users on premises in Skype for Business Server or Lync Server 2013, and then move them online. For more information, see Plan hybrid connectivity between Skype for Business Server and Skype for Business Online and the special considerations section of Enable the users for Enterprise Voice on premises (performed while the users are homed on-premises).
All users must be created in Active Directory on premises and synchronized to Microsoft 365 or Office 365 using the supported version of Microsoft Entra Connector. You cannot enable users for Phone System in Office 365 who were created directly in Microsoft Entra ID. If you want to enable Phone System with on-premises PSTN connectivity for a user who was created in Microsoft Entra ID, you'll need to create a new account for that user in your on-premises AD, configure the account on-premises, and then synchronize the account using a supported version of the Microsoft Entra Connector tool.
Enabling a user for Phone System with on-premises PSTN connectivity and then moving them to Skype for Business Online requires the following steps:
Enable the users for Enterprise Voice on premises (performed while the users are homed on-premises).
Assign a Voice Routing Policy (performed while the users are homed on-premises).
Synchronize users to the cloud and assign licenses (performed using Office 365).
Enable users for Enterprise Voice online and Phone System Voicemail (performed using Remote PowerShell.