Unable to verify sign-in after deleting Microsoft Authenticator app

If the Microsoft Authenticator app was deleted and sign-in can no longer be verified, recovery depends on what other sign-in methods or admin options are available.

1. Try alternative sign-in methods

• Go to the sign-in page and look for options such as:
  • SMS/phone call verification
  • Email verification
  • Security questions or backup methods
• If another method works, sign in and then:
  • Go to https://aka.ms/mysecurityinfo
  • Delete the old Authenticator app method and re-add Microsoft Authenticator on the current device.

2. If five Authenticator devices are already registered If the error indicates that the maximum of five devices are already registered for the Authenticator app, an admin must remove old Authenticator registrations:

• Admin signs in to https://aka.ms/mysecurityinfo for the affected user and deletes some or all existing Authenticator sign-in methods.
• Or a Global Administrator deletes the user’s Authenticator methods via Microsoft Graph as described in the “Solution 2” steps:
  • Use Graph Explorer as Global Admin.
  • Run GET https://graph.microsoft.com/beta/users/<user-principal-name>/authentication/microsoftAuthenticatorMethods to list methods.
  • Copy each id to delete.
  • Run DELETE https://graph.microsoft.com/beta/users/<user-principal-name>/authentication/microsoftAuthenticatorMethods/<authenticator-id-guid> for each method.
  • After deletion, the user can sign in and re-register MFA.

3. If locked out and another Global Admin exists

• Another Global Administrator can reset MFA so the user can re-register Authenticator:
  • In Azure portal → Microsoft Entra ID → Users → select the user → Authentication methods → Require re-register multifactor authentication.
  • Next sign-in will prompt to set up MFA again, including Microsoft Authenticator on the new device.

4. If locked out and there is no other Global Admin If the affected account is the only Global Administrator and no other MFA method works:

• Microsoft Data Protection / Tenant Recovery support must reset MFA from the backend.
• This is done by contacting Microsoft Support by phone (Global Customer Service) and clearly stating that the only Global Admin is locked out due to Authenticator loss and needs MFA reset.
• If direct support contact is blocked because sign-in is impossible, a temporary trial tenant can be created only to open a support ticket, as described in the Q&A guidance, and request escalation to the Data Protection team for the original tenant.

5. If the issue is just “Authentication did not complete” If the app is installed but sign-in fails with “Authentication did not complete,” check:

• Authenticator app is unlocked.
• Notifications are enabled and not silent.
• The app is updated to the latest version.
• Device has a working internet connection (try switching Wi‑Fi/mobile data).
• Device date and time are correct.

Once access is restored, add at least one backup MFA method (phone/SMS) and consider enabling cloud backup in Authenticator so that future device loss does not cause lockout.

References:

• How to sign out from Authenticator
• Can't set up MFA because five devices are already registered to use an authenticator app
• Troubleshoot problems with Microsoft Authenticator
• Back up account credentials in Microsoft Authenticator
• How Do I Regain Access to My Account After Losing Access to Microsoft Authenticator? (Urgent Request). - Microsoft Q&A
• Global Admin Locked out - Microsoft Q&A
• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A
• I need to reset my mfa methods - Microsoft Q&A
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A