Microsoft has announced that it will stop supporting Exchange Web Services (EWS) for non-Microsoft applications in Exchange Online from October 1, 2026. This means that third-party apps that use EWS to access Exchange Online data will no longer be able to do so after this date.
What is Exchange Web Services and why is it being retired?
Exchange Web Services is a web-based protocol that allows applications to communicate with Exchange Online servers and access email, calendar, contacts, and other data. EWS was introduced in Exchange Server 2007 and has been used by many third-party apps to integrate with Exchange Online.
However, Microsoft has stopped making feature updates to EWS in Exchange Online since 2018 and has advised developers to migrate to Microsoft Graph, which is the unified API for accessing Microsoft 365 data and services. Microsoft Graph offers more features, functionality, and security than EWS, and is the preferred way to access Exchange Online data.
Microsoft has decided to retire EWS for non-Microsoft apps in Exchange Online to ensure more secure, reliable, and performant experiences for users and developers. This change will not affect EWS in Exchange Server, which will continue to be supported. It will also not affect Outlook for Windows or Mac, Teams, or any other Microsoft product that uses EWS.
How will this affect developers and users?
Developers who have built apps that use EWS to access Exchange Online data will need to migrate their apps to Microsoft Graph before October 1, 2026. Otherwise, their apps will stop working after this date. Microsoft has provided guidance and resources for migrating from EWS to Microsoft Graph on its developer blog.
Users who rely on third-party apps that use EWS to access their Exchange Online data will need to check with their app providers whether they have plans to migrate to Microsoft Graph. If not, they will need to find alternative solutions or switch to Microsoft apps that support Microsoft Graph.
What are the benefits of migrating to Microsoft Graph?
Microsoft Graph is the modern and recommended way to access Microsoft 365 data and services. By migrating from EWS to Microsoft Graph, developers and users can enjoy the following benefits:
- Access more data and features: Microsoft Graph provides access to more types of data and features than EWS, such as archive mailboxes, user configuration, and exchange online management. Microsoft Graph also supports new scenarios and capabilities that are not available in EWS, such as webhooks, delta queries, batching, and more.
- Stay up-to-date and secure: Microsoft Graph is constantly updated with new features and functionality, while EWS is no longer receiving feature updates. Microsoft Graph also offers better security and compliance than EWS, such as conditional access, application permissions, and audit logs.
- Simplify development and integration: Microsoft Graph provides a single endpoint and a consistent API for accessing Microsoft 365 data and services, while EWS requires multiple endpoints and protocols. Microsoft Graph also provides SDKs for various languages and platforms, as well as tools and documentation to help developers get started quickly.
