Introduction

Microsoft has announced the deprecation of Exchange Web Services (EWS) in Exchange Online, effective October 1, 2026. To facilitate a smooth transition to Microsoft Graph, the Microsoft 365 Admin Center now offers EWS Usage Reports, providing administrators with critical insights into current EWS dependencies.

Background on EWS Deprecation

EWS, introduced with Exchange Server 2007, has been a pivotal API for accessing mailbox items such as emails, contacts, and calendar events. However, in 2018, Microsoft ceased feature updates for EWS, signaling a shift towards more modern, secure, and scalable solutions like Microsoft Graph. The official retirement date for EWS in Exchange Online is set for October 1, 2026. (devblogs.microsoft.com)

Introduction of EWS Usage Reports

To assist organizations in identifying and managing their reliance on EWS, Microsoft has integrated EWS Usage Reports into the Microsoft 365 Admin Center. These reports offer detailed insights into:

  • Application Identification: Pinpointing third-party applications utilizing EWS.
  • Usage Metrics: Analyzing call volumes and specific actions performed via EWS.
  • Trend Analysis: Monitoring usage patterns over selected periods.

Accessing these reports is straightforward:

  1. Log into the Microsoft 365 Admin Center.
  2. Navigate to the "Reports" section.
  3. Select "Usage" and then choose "Exchange > EWS Usage."

These reports are available to worldwide tenants, with specific guidance provided for government or sovereign cloud users. (techcommunity.microsoft.com)

Implications and Impact

The deprecation of EWS necessitates proactive planning from IT departments and developers. Key considerations include:

  • Security Enhancements: Transitioning to Microsoft Graph aligns with Microsoft's Secure Future Initiative, offering improved security features. (devblogs.microsoft.com)
  • Feature Parity: While Microsoft Graph covers many EWS functionalities, some gaps remain, such as access to archive mailboxes and public folders. Microsoft is actively working to address these gaps. (learn.microsoft.com)
  • Application Migration: Organizations must assess and update applications dependent on EWS to ensure compatibility with Microsoft Graph.

Technical Details and Migration Strategies

To facilitate migration:

  • EWS Code Analyzer: Microsoft provides an open-source tool to identify EWS dependencies within codebases, aiding in the transition to Microsoft Graph. (devblogs.microsoft.com)
  • Microsoft Graph API: Developers are encouraged to familiarize themselves with Microsoft Graph, which offers RESTful endpoints for accessing Microsoft 365 services.

Conclusion

The introduction of EWS Usage Reports is a strategic move by Microsoft to support organizations in transitioning from EWS to Microsoft Graph. By leveraging these reports and planning migrations proactively, organizations can ensure continued functionality and enhanced security in their Microsoft 365 environments.