Thank you for reaching out to the Microsoft Q&A Forum. I understand how frustrating this is when "Downloading…" spinner for hours, especially when you can see new mail arriving.
Here are some steps that you could try:
1. Check the mailbox directly on Outlook on the web
This confirms whether the issue is app‑only.
- Sign in at https://outlook.live.com
- If emails open normally there, the mailbox is fine and the issue is isolated to the iOS app.
2. Update Outlook for iOS
- Make sure the app is fully up to date from the App Store.
- Also ensure iOS Mail or Outlook app has Background App Refresh enabled in your phone's Settings
3. Reset the mobile app
- Go to Outlook app on your phone
- Tap your profile icon (top-left) > Settings > Accounts > Choose your account
- Scroll down and select Reset Account
- Sign back in and test again
4. Remove and re-add the account
- In the same place, tap Remove account
- Close the app completely, then reopen Outlook.
- Tap Add account, and sign in again.
For more details, you can see Get in-app help for Outlook for iOS and Android - Microsoft Support
If the steps above don't work, please feel free to let me know how it goes so I’ll help you further. Thank you for your understanding and patience.
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