In 2018, Microsoft announced that we were no longer making feature updates to Exchange Web Services (EWS) in Exchange Online, and we advised developers to move to Microsoft Graph.
Today, we are announcing that on October 1, 2026, we will start blocking EWS requests from non-Microsoft apps to Exchange Online.
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.
Despite today’s announcement, EWS is still available and supported for use in production environments. But we strongly suggest migrating to Microsoft Graph to access Exchange Online data and gain access to the latest features and functionality.
Today’s announcement and the retirement of EWS apply only to Microsoft 365 and Exchange Online (all environments); there are no changes to EWS in Exchange Server. Further, the changes in Exchange Online do not affect Outlook for Windows or Mac, Teams, or any other Microsoft product.
Link to Microsoft Article is Here