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Exchange Team Blog
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Upcoming API Deprecations in Exchange Web Services for Exchange Online

The_Exchange_Team's avatar
The_Exchange_Team
Platinum Contributor
Oct 05, 2021

Update 1/20/2022: We have edited this post for clarity based on customer feedback.

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.

In August 2018, we announced that we were no longer going to actively invest in Exchange Web Services (EWS) APIs for Exchange Online. We also gave a strong recommendation to start migrating to Microsoft Graph for Exchange Online data access.

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 deprecating these APIs to begin the process of reducing the surface area of the EWS protocol for maintenance and security purposes. Support for these APIs will no longer exist after March 31, 2022.

The list of deprecated APIs is at the end of this post. We will introduce sunset headers in the response for these APIs that are marked for deprecation.

We have already sent Message Center posts to tenants using these low volume, and now deprecated APIs. If you did not already receive a Message Center post, you will not be impacted by this change.

Over time, we will identify additional APIs for deprecation when and where we see adequate parity with Microsoft Graph APIs. We are also working hard on addressing feature gaps and building parity between EWS and Microsoft Graph APIs. We strongly urge our ecosystem partners accessing Exchange Online data to migrate to Microsoft Graph APIs.

We previously announced that we planned to prevent registration of new apps in Azure with EWS permissions, but based on your feedback we have decided to postpone this plan for the time being.

EWS is a legacy API surface that has served us well, but no longer meets the security and manageability needs of modern app development. We strongly urge our ecosystem partners accessing Exchange Online data to migrate to Microsoft Graph APIs.

APIs scheduled for deprecation:

The Exchange Team and Microsoft Graph Team

Updated Jan 20, 2022
Version 5.0

78 Comments

  • WGroenestein's avatar
    WGroenestein
    Copper Contributor

    I think it would be good for Microsoft to provide some more clarification on the following statement "Today, we are announcing that we are going to remove the ability to create new EWS apps starting September 30, 2022.". Does it mean we can no longer add the "EWS.AccessAsUser.All" permission to new Azure Active Directory apps? If so, does it apply to both UI and API operations? How does Microsoft propose developers deal with needing to support both Exchange Online and Exchange On-premises ?

  • Peter Kozak's avatar
    Peter Kozak
    Brass Contributor

    This is a major announcement and has the potential to impact every Microsoft customer from the point onward where no new EWS App Registrations are possible.

     

    Right now, the Exchange Web Services API is the only way to get full-fidelity (preserving all properties) email information into and out of Office 365 (see MS-OXWSBTRF). Without this capability, 3rd Party applications addressing backup, eDiscovery, and migration (including Tenant-to-Tenant) will simply not be possible anymore! Also, even if the Graph API is extended to support the missing methods, will MSFT switch to the same "paid" model to use the Graph API as with Teams?  

     

    Imagine the implications of an acquisition or divestiture scenario, where one needs to consolidate tenants and/or on- or offboard legacy data. Cost and Time implications might get enormous, and a lot of restructuring projects will never reach an ROI if suddenly the project costs and timelines multiply.

  • Tom_R_'s avatar
    Tom_R_
    Brass Contributor

    Completely agree wit JonasBack and stukey 

     

    Microsoft needs to provide reporting so that we can easily identify the apps that are utilizing the impacted EWS APIs (and EWS more generally). I don’t think we can rely on the Azure AD Sign-In logs as they only allow you to filter on Client App, which for EWS is only listed for Basic Authentication connections.

  • MichelZCF's avatar
    MichelZCF
    Brass Contributor

    What does that mean, "Today, we are announcing that we are going to remove the ability to create new EWS apps starting September 30, 2022."?

    You mean you can't create Azure AD apps anymore with EWS permissions? You're kidding, right?

  • stukey's avatar
    stukey
    Iron Contributor

    I agree with Jonas, Microsoft needs to provide reporting so that we can easily identify the apps that are utilising the impacted EWS APIs (and EWS more generally). I don’t think we can rely on the Azure AD Sign-In logs as they only allow you to filter on Client App, which for EWS is only listed for Basic Authentication connections.

     

    Also how do these changes impact the Outlook for Windows and Outlook for Mac clients, since it’s my understanding that both clients still utilise EWS to connect to Exchange Online for some functionality (especially Outlook for Mac - current version, not the new UI version which uses Microsoft Sync Technology).

  • Renaud_B's avatar
    Renaud_B
    Copper Contributor

    Hello, the main issue we face today is that graph API does not cover all methods covered by EWS. It will be easier to move to graph API if we did not miss some of it. We are now in a situation where we need to do heavy developments using Graph API and EWS. knowing that we will need to do some more developments when those missing features will be covered by graph API. Hope we can use Graph API fully soon. thanks

  • JonasBack's avatar
    JonasBack
    Iron Contributor

    Way to go! Are there any plans to provide insights if these particular API:s are in use in our tenant(s) so we know if we will be affected of these depreciations?