|Today we are announcing the deprecation of the 25 least used APIs of EWS for Exchange Online (as determined by the call volume into the service).
We are retiring these APIs to begin the process of reducing the surface area of the EWS protocol for maintenance and security purposes. After the retirement, support will end for these APIs.
In the coming months we will send Message Center posts to tenants we can see are using these low volume, and now deprecated APIs.
We will also remove the ability to register new apps in Azure with EWS permissions starting September 30, 2022. Apps registered before this date, any API not mentioned in this, or subsequent announcements, will not be impacted.
Over the last few years, we have invested heavily in Microsoft Graph to enable developers to access the rich data available in Microsoft 365. Microsoft Graph, along with OAuth 2.0, provides increased security and seamless integration with other Microsoft cloud services.
- Timing: Late March, 2022
- Action: We strongly urge you and our ecosystem partners that access Exchange Online data to migrate to Microsoft Graph APIs.
How this will affect your organization:
We will introduce sunset headers in the response for these APIs that are marked for retirement. As per our retirement policy, we will decommission these APIs by March 31, 2022.
Note: This set of retirement is the first in a series of steps we will take as we sunset EWS for Exchange Online. Over time, we will identify additional APIs for deprecation when and where we see adequate parity with Microsoft Graph APIs.
The list of APIs that will be retired is available here.
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