Forum Discussion
How to Find Active EWS-Based Apps in a Microsoft 365 Tenant
Microsoft will retire Exchange Web Services (EWS) from Exchange Online on October 1, 2026. A new usage report helps tenants understand what apps use EWS. Many of the apps are likely to be first-party (Microsoft) apps, but some might be third-party apps developed externally or internally. Those apps need to be retired or upgraded to use Graph APIs. Time is slipping away to do the work.
https://office365itpros.com/2025/04/29/exchange-web-services-apps/
5 Replies
Try searching Google or Bing to find any references to the GUID you see. If you can’t find anything, the app is likely an internal Microsoft app.
Hi TonyRedmond
Thanks for replying. I have searched the GUID's with Google, but no results show up. So these would be internal Microsoft apps.
Some Microsoft apps are still using EWS (for example Microsoft Teams, Microsoft Outlook or Office 365 Exchange Online are on the EWS Usage report). Do we have to take action for these apps? Or can we ignore them and will Microsoft change these apps so these will not use EWS anymore?
Kind regards,
ArjanMicrosoft will take care of its own apps by October 2024. The ones you've got to worry about are those from ISVs or internally-developed apps.
Hi TonyRedmond
Thanks for this usefull information! I used the information you placed on your website to identity apps that still using EWS. But some of the apps mentioned in the usage report are not show up when I search them by ID. Is there a possibility to identity these apps another way?
Kind regards,
Arjan
