Using Outlook for iOS for personal email and calendar management
Hi, Simon Cloke
Since the old inbox is still visible, the new iPhone may be showing cached messages while the Outlook app is no longer syncing with the mail server.
Here are some suggestions you can try:
First, open Safari and sign in at Outlook on the web. Send yourself a test message. If this works, the mailbox is fine and the problem is limited to the iPhone.
If using the Outlook app, open Outlook > profile picture > Settings > select the email account > Reset Account. Then fully close Outlook and reopen it. This refreshes the app’s connection without deleting your mail.
Open the App Store, search for Microsoft Outlook, and install any available update. Also check Settings > General > Software Update for an iOS update.
Check Settings > Cellular > Outlook and make sure cellular data is enabled. Also test Outlook on both Wi-Fi and cellular data.
If it still does not sync, delete and reinstall the Outlook app from the App Store, then sign in again. Your messages remain stored online.
For a work or school account, the organization may require device enrollment or the Outlook app, so the Microsoft 365 administrator should check Intune or Conditional Access requirements.
Thank you for your patience in reading, I hope this information has been helpful to you.
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