Microsoft has said that it will be shutting down the Exchange Web Services Application Programming Interface for Exchange Online and Office 365, in approximately three
Exchange Web Services (EWS) is a cross-platform Application Programming Interface (API) for developing apps that can access mailbox items such as email messages, meetings, and contacts. Access to these resources can be obtained through several options, including Exchange Online as part of Office 365, and on-premises editions of Exchange (starting with Exchange Server 2007). “Today, we are announcing that on October 1, 2026, we will start blocking EWS requests from non-Microsoft apps to Exchange Online,” Microsoft said in a blogpost on Tuesday. “While the EWS components of the service will continue to receive security updates and certain non-security updates, product design and features will remain unchanged. This change also applies to the EWS SDKs for Java and .NET, as well,” it added.