[Upcoming changes] Exchange Web Services API for Office 365

Exchange Web Services (EWS) was launched as a part of Microsoft Exchange 2007 as a SOAP based API that allows access to Exchange and Exchange Online data. Starting July 3, 2018, Exchange Web Services (EWS) will no longer receive feature updates. While the service will continue to receive security updates and certain non-security updates, product design and features will remain unchanged. This change also applies to the EWS SDKs for Java and .NET as well. While we are no longer actively investing in it, EWS is still available and supported for use in production environments.

As we make progress on this journey, we have continued to evaluate the role of Exchange Web Services (EWS). Also we are sharing our plans to move away from Basic Authentication access for EWS over the next two years, with support ending Oct. 13, 2020. These plans apply only to the cloud-based Office 365/Exchange Online products; there are no changes to EWS capabilities of on-premises Exchange products.

Here’s the related documents:

• If you’re EWS developer then please refer: https://dev.office.com/blogs/upcoming-changes-to-exchange-web-services-ews-api-for-office-365 
• If you’re Exchange ITPros then refer: https://blogs.technet.microsoft.com/exchange/2018/07/03/upcoming-changes-to-exchange-web-services-ews-api-for-office-365/

In this scenario, we strongly suggest migrating to Microsoft Graph to access Exchange Online data and gain access to the latest features and functionality.

Hope this helps.