Required Setting Change for Microsoft Office 365 Customers

In October 2020, Microsoft® retires basic authentication for Microsoft Office 365® and Exchange Online. To maintain your Lightning Sync connection, Office 365 customers who use the service account connection method must move to the OAuth 2.0 connection method.

Where: This change applies to Lightning Experience, Salesforce Classic, and all versions of the Salesforce app in Professional, Enterprise, Performance, Unlimited, and Developer editions.

Who: This retirement affects only Office 365 customers who use a service account to connect to Salesforce. Microsoft hasn’t announced retirement for basic authentication for Exchange 2016® or Exchange 2013®. Therefore, customers on those servers can continue using the service account connection method and basic authentication to connect to Salesforce. As of Spring ’20, Lightning Sync also supports NTLM authentication for those servers. See NTLM Authentication Protocol Supported For Microsoft Exchange 2016 and 2013.

Why: The service account connection method requires basic authentication to maintain your users’ connections between Exchange and Salesforce. When the Microsoft retirement takes effect, it interrupts your connection, causing contacts and events to stop syncing. To avoid sync interruption, work with the Microsoft admin or IT professional at your company to migrate to the OAuth 2.0 connection method before October 2020.

How: For steps on how to prepare for retirement, see Change Your Lightning Sync Connection Method before Basic Authentication Retirement for Microsoft Office 365 and Exchange Online.