Action Required: Update active Exchange Web Services Applications

As far as I know, the iOS and iPadOS Mail apps are fine and do not use EWS anymore. The Mail app on macOS does rely on EWS for some parts and would no longer work with EWS disabled.

Yesterday I applied Microsofts Baseline security mode on my Microsoft 365 subscription. This blocks EWS ahead of the global disabling of this on Exchange Online as of October 2026. As expected, the Exchange account within the Mail app on macOS stopped working. The Mail app on iOS is still working fine.

As you would expect, Microsoft and Apple are aware of this. I received a message this morning in the M365 admin centre.

...

How this affects your organization:

In October 2026 we will begin disabling EWS on all M365 tenants worldwide. EWS Applications that have not been migrated will stop functioning.

The following applications on your tenant use EWS:

Entra Application ID

Apple Mail for Mac (f8d98a96-0999-43f5-8af3-69971c7bb423)

...

Note on Apple Mail for Mac

Apple Mail for Mac and related applications are some of the most popular EWS applications. We are working closely with Apple to update these applications. In order to run your tenant in the most secure configuration today, users of Apple Mail for Mac would have to switch to an alternative like Outlook for Mac until the applications have been updated.

Still surprising that this has not been solved already, but hopefully Apple will fix this before October 2026. 🤞

I am leaving EWS disabled for now and will use Outlook for Mac until this is fixed.

Our Baseline Security mode detects the Apple Internet Accounts (AppID f8d98a96-0999-43f5-8af3-69971c7bb423) which is for the native mail app in iOS/iPadOS and it uses EWS.

I'm assuming it's the case for mattias152 and others. I spoke with an Apple Senior Advisor, they stated uncertainty of new changes or when, but to call back at a later date / look out for Apple communications.

Apple will not see "action requests" in this user-to-user forum setting. To get pertinent needs to an Apple employee, please use this:

https://www.apple.com/feedback/mail/

The Jan 28 post by "NLA" in this Microsoft forum is interesting:

https://learn.microsoft.com/en-us/answers/questions/5628387/the-operation-couldn-t-be-completed-%28com-apple-acc

Quick FYI update on this one: macOS 27.2 apparently had hooks for the Graph API, which can now be turned on in macOS 27.3 using an AppleSeed for IT profile. See this forum at Macrumors and/or the AppleSeed Resources. I'm not sure if this means the feature will be turned on and supported in 27.3, but it is a step in the right direction.

Apple need to get this sorted, as for many of us using Microsoft's recommended security configuration, we can no longer use the native Calendar or Mail apps. I have submitted a bug report to Apple, but I'm not holding my breath.

I just ran the Find-EwsUsage.ps1 script provided by Microsoft and it reported that roughly 80 out of 400 users in a Microsoft 365 tenant uses EWS for the Apple Internet Accounts Enterprise application. This organization does not use Mac so we must assume that these are the iOS native mail app users. Can I ignore this information and expect these mail clients to continue working, or will they stop working on October 1st?

My college has already kicked Apple Mail off of their Office365 service. Pretty sure my work is going to do the same October 1st. Apple, it'd be great if we could get some work done on Mail so the rest of us could keep getting our work done.

how do we get Apple to expedite this? How do we report this bug?

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Do anyone have news for this topic?

Any updates on when they're gonna fix this?

Well, now Apple has essentially eliminated Macs from most office ecosystems. They've had most of 2026 to get ahead of this, but nope. Now I can't get my work E-mail or calendar on my Mac.