Microsoft Axes Outdated EWS Tech in 2026
Microsoft has announced that it will retire its Exchange Web Services (EWS) technology on October 1, 2026. This means that applications and email clients using EWS will no longer be able to connect to Microsoft 365 mailboxes after this date.
EWS is an older technology used by some applications to access Exchange Online services such as email, calendars, contacts, mailbox automations, service accounts, and workflow integrations. While most Microsoft 365 applications have already transitioned to modern technologies, some third-party applications, custom integrations, and automated processes may still rely on EWS.
Users of Apple Mail will be impacted by the retirement of EWS, as it uses this technology when connected to a Microsoft 365 or Exchange Online mailbox. To resolve this issue, users should migrate to Microsoft Outlook for Mac or another supported Microsoft 365 client.
Legacy Outlook for Mac users will also no longer be able to function with Exchange Online after the retirement of EWS. These users are advised to switch to New Outlook for Mac, which uses modern Microsoft 365 technologies and does not depend on EWS.
Other applications and integrations that rely on EWS may experience service interruptions as well. Application owners are advised to review and update any applications, scripts, services, or integrations that use EWS to ensure they support modern authentication technologies and/or Microsoft Graph.