Synchronize calendar from outlook to ios calendar with MAM

We are a BYOD environment using MAM-only (no MDM enrollment) on personal iPhones. Our users need work calendar events visible in the native iOS Calendar app for Apple Watch and Siri functionality which is the same experience Android users already have.  

We have correctly configured:

App Protection Policy: Sync policy managed app data with native apps = Allow

App Configuration Policy: com.microsoft.outlook.Calendar.ExternalCalendarSyncEnabled = True (Boolean)

App Configuration Policy: Sync Calendars = On

Despite correct configuration, the Sync Calendars toggle never appears in Outlook for iOS. This is a significant gap for organizations running BYOD programs where full MDM enrollment is not appropriate. Android parity already exists. Please bring this to iOS.

Hello,

I came across this thread yesterday with the same question and think I have now solved the problem. So I will post my provisional solution here. My solution is to distribute a configuration policy via Intune that uses email as a template and has the following settings:

Email server: outlook.office365.com

Account name: Managed Account

User name attribute from Microsoft Entra ID:

User principal name

Email address from Microsoft Entra ID: Primary SMTP address

Authentication method: User name and password

SSL: Enable

OAuth: Enable

Exchange data to synchronize: Calendar and contacts only

Allow users to change synchronization settings: No

I simply used the official Microsoft documentation here, which is a bit older but still works.

This distributes the email profile without allowing users to edit or delete it.

The other important setting concerns the Conditional Access Policy.

The conditional access rule blocks logins to unmanaged applications. The following settings were configured for this purpose:

• Target resource: All resources
  • Excluded: Office 365, Apple Internet Accounts, Microsoft Intune, Microsoft Intune Enrollment
• Conditions:
  • Device platforms: Android/iOS

Access controls: Grant access -> App protection policy required.

The app protection policy is very standard, so I don't think I need to go into any further detail here. The only important thing here is that all "Microsoft apps" are specified under Public Apps.

And now I'll explain why the CA has to be set up the way I did. At first, I did not exclude O365, and logging in to Apple Internet Accounts still did not work (despite the exception) because the login redirects to Exchange Online, which in turn requires the app protection policy. The app protection policy is still required, but the O365 apps are no longer enforced by the CA rule. It is still applied, however.

These settings now prevent Apple Mail from using the SMTP address in the distributed mail profile. The good thing is that this setting can no longer be edited by users, and no further profiles with the same SMTP address can be created.

I haven't been able to test everything yet, but the basic Microsoft apps work fine and the Apple calendar and contacts sync perfectly.

Hi @KIMDER

Welcome to Q&A Community! 

Thank you for reaching out and for your patience. 

Based on the latest Microsoft documentation, there are currently no updates regarding this feature. At the moment, calendar synchronization with the native iOS Calendar app is still not supported when using Intune MAM (Mobile Application Management). This functionality is currently only available for Android devices. 

For reference (as of 04/29/2025): Deploying Outlook for iOS and Android app configuration settings in Exchange Online | Microsoft Lea… 

There are a few key reasons why this feature is still not available on iOS when using Intune MAM, including: 

1. Apple’s App Sandboxing Model 
2. Microsoft Intune App Protection Policies 
3. No Supported API for Secure Sync 
4. Security & Compliance Requirements 

I understand this may cause inconvenience, and I truly appreciate your understanding. As a forum moderator, I'm afraid that I don’t have the permissions to make product changes, therefore, I strongly encourage you to submit feedback through the Outlook app or Microsoft Feedback Portal. Many users have shared that feedback submissions help influence future updates. 

Available options for now: 

• Use the Outlook mobile app for full calendar functionality. 
• If your organization allows, you can access your calendar via Outlook on the web. 

Thank you for your understanding and for helping us improve by sharing your feedback. Your patience and kindness are highly appreciated. 

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