Important information: EWS is being discontinued in Exchange Online
Microsoft has announced that Exchange Web Services (EWS) will be phased out in Exchange Online. Starting in October 2026, EWS will be blocked by default in many tenants, and it will be fully disabled on April 1, 2027. This change affects Microsoft 365 / Exchange Online only, not on‑premises Exchange servers.
What does this mean for ExMixedFolders?
What does this mean for ExMixedFolders? ExMixedFolders currently uses EWS to access mailboxes in Exchange Online. Once EWS is disabled in your Microsoft 365 tenant, ExMixedFolders will no longer be able to work with Exchange Online mailboxes. Synchronization of folders, contacts, appointments or tasks via EWS will then no longer be possible.
Nothing changes for on‑premises Exchange servers: EWS will remain available there, and ExMixedFolders can continue to be used as before.
What does this mean for EEAttachments?
EEAttachments also relies on EWS to process Exchange Online mailboxes. When EWS is disabled in your tenant, EEAttachments will no longer be able to retrieve emails and attachments from Exchange Online. Processing attachments from on‑premises Exchange servers will still be possible, because EWS remains available on‑premises.
What should you do now?
- Check whether ExMixedFolders and/or EEAttachments in your tenant are still using EWS against Exchange Online.
- Plan a timely migration to Microsoft Graph, as Microsoft is permanently shutting down EWS in Exchange Online and no exceptions will be possible after April 2027.
- If you need to continue using EWS temporarily, your administrator can keep EWS enabled in Exchange Online at the tenant level for a limited period and maintain an allow‑list for EWS applications. Please note, however, that the final shutdown will still take place by 2027 at the latest.
- Unfortunately, some features are not available in Microsoft Graph; this also includes access to Public Folders. As an alternative, Shared Mailboxes may be used in some scenarios.