Cell WordStrange:

Hello Sid Kraft,

Thank you for posting on Microsoft Q&A.

Based on your description, it appears that repeated sign-in attempts may have triggered a temporary security "lock" on the verification system. To help you break this loop and regain access, I recommend the following approach: 

1. Wait for 48 hours
2. Use the Sign-In Helper: Go to the Microsoft Sign-In Helper on a computer or tablet. For a better chance of success, disconnect from Wi-Fi and use your mobile data (LTE/5G) or a personal hotspot, as this provides a fresh connection that hasn't been flagged by security filters. 
3. Refresh the Mobile App 

Once you have successfully logged in via a web browser, uninstall the Outlook app from your phone, restart your device, and then reinstall it from the App Store. This clears any temporary memory and lets you start fresh with a clean login. 

I truly hope these steps help you regain access without any more stress. Please let me know how it goes! 

To regain access to Outlook on the phone, the steps depend on what kind of account is being used and where the sign-in is failing.

1. If this is a personal Outlook.com / Hotmail / Live account

• Use the Microsoft sign-in helper in a browser first to fix the account, then return to the Outlook app:
  • Go to the sign-in helper: Start.
  • Enter the email address or mobile number used for the account.
  • Follow the on-screen steps; if a problem is detected, it will tell what to do, and if not, it will guide through self-help recovery.
• If the app keeps looping or asking for codes that don’t work, remove the Outlook app from the phone and install the latest version again from the app store: download the latest version.

2. If this is a work or school Microsoft 365 account

• If the account is provided by an organization, the IT admin may have blocked or restricted Outlook Mobile access. In that case, contact the organization’s IT administrator and provide the exact error text.
• If self-service password reset is allowed, reset the password here and then sign in again in the Outlook app: Reset password.

3. If the error is “Access Denied” or similar on Outlook Mobile

• Some accounts are explicitly denied access to Outlook Mobile by policy. In that case, the only resolution is through the IT administrator for that account, as support agents cannot unblock it.

4. If the account is a non-Microsoft email (Gmail, Yahoo, iCloud) in Outlook

• Sign-in and verification problems for those accounts must be fixed with the email provider (Google, Yahoo, Apple, etc.). After the account works in a browser, remove and re-add it in the Outlook app.

5. If Outlook Mobile itself is misbehaving (crashing or stuck)

• Make sure the phone meets app requirements, has enough storage, and has a stable data/Wi‑Fi connection.
• If the app crashes or behaves strangely, clear the app/browser cache on the phone, uninstall Outlook, restart the phone, then reinstall Outlook from the app store.

If none of these paths work and this is an Outlook.com account, use the Outlook.com help entry point for additional support options: click Help in Outlook.com and, if self-help does not fix it, scroll to Still need help? and choose Yes to reach support, or use the “can’t sign in” link if sign-in is not possible.

References:

• Can't sign in to the Outlook mobile app
• Troubleshoot Outlook mobile issues
• Access Denied: Login Error
• Outlook prompts for phone number for Outlook.com accounts
• Can't sync calendar and contacts with my phone or tablet