After announcing in 2018 that it no longer planned feature updates for Exchange Web Services (EWS) in Exchange Online, Microsoft said this week that starting on Oct. 1, 2026, it will block EWS requests from non-Microsoft apps to Exchange Online. It recommends that developers move to Microsoft Graph to access Exchange Online data.
However, it stressed, “the 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.”
