iOS Outlook stuck 'downloading your messages'

Dear Héctor,

As a forum moderator, I am not able to access your account or delve into the backend systems to diagnose and fix this for you. My role here is limited to providing general guidance and solutions for users to implement themselves. Since Outlook works on your laptop and you've already reinstalled and reset the app, the problem is most likely limited to your phone's connection to the account, not the mailbox itself. A few quick checks you can try on the phone:

1. Test the account in a browser: Open Safari, go to outlook.cloud.microsoft and sign in. If your mail shows there, the account works on that device and the problem is within the app.
2. Switch networks: Try Wi-Fi and mobile data separately, since some work or public networks block mobile mail sync.
3. Check iOS settings: Go to Settings > Outlook and make sure Mobile Data and Background App Refresh are turned on.
4. Check for required apps: Some organizations require Microsoft Authenticator or Intune Company Portal on the phone before Outlook can sync. If you see any prompt about this, follow it, or ask IT whether it applies.

If none of these help, please pass these points to your IT team, as they're the usual fix for this:

• Microsoft Entra sign-in logs for Outlook mobile failures.
• Conditional Access results and device-compliance requirements.
• Whether Outlook mobile access is enabled for your mailbox.
• The mobile-device partnership in the Exchange Admin Center.
• Whether the mailbox has an unusually large or malformed item causing the initial mobile synchronization to stall.

The administrator can remove the stale mobile-device partnership associated with your iPhone and then have you add the account again. Do not repeatedly reinstall Outlook before IT checks the account-side records.

If administrator checks show no policy or sign-in failure, they can create a service request with Microsoft Support. A technical support engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis. For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin. 

For additional assistance, use this link to find the appropriate contact number from your region: Contact Microsoft customer support | Microsoft Support 

I truly hope you get your issue resolved swiftly. Please know that even though I can't directly intervene, directing you to the correct, specialized support is the most effective help I can provide from my position. Thank you for your patience and understanding. Please let me know if you need anything else. Wishing you all the best. 

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