Hello @Scott Jones
From what you described: Each time you open the Microsoft Outlook app on your iPhone, you’re prompted to sign in again. After you enter your credentials, Outlook recognizes your email address and allows you to access your mailbox normally, but the sign‑in request keeps reappearing every time you reopen the app. Functionally, email still works, but the recurring sign‑in notification is disruptive and concerning for you.
In this case, this usually happens due to authentication or token‑storage issues on the mobile device.
In the meantime, here are some safe first‑line steps you can try on your own:
1/ Update everything
Make sure both iOS and the Outlook app are fully up to date.
2/ Remove and re‑add the account
- In Outlook -> Settings -> Account -> select your account -> Remove Account
- Close the app completely, reopen it, and add the account again.


3/ Check Keychain & device security
- Ensure Face ID/Touch ID and device passcode are enabled.
- Go to iOS Settings -> Passwords & Accounts and confirm Outlook access isn’t restricted.
- Disable and re‑enable Outlook background access
- iOS Settings -> General -> Background App Refresh -> toggle Outlook off, restart phone, then turn it back on.
Note: The steps and button names may vary slightly depending on your iOS version, device model, or Apple updates.
4/ Sign out of Microsoft apps temporarily
If you’re signed into other Microsoft apps, sign out of all of them, then sign back into Outlook first.
If you still need my assistance, please come back with screenshots or any additional details so I can review it again and see if there’s anything more I can help you with.
Have a nice day!
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