Authenticator

Question

I have a new phone and had to delete the old authenticator to set a new one with my job and now I cannot get into some website that uses this to allow access. Is there something I can do to retrieve my old access.

Answer 1

If the old phone and its Authenticator app were deleted before backup/transfer, the old “access” itself cannot be restored, but access to the accounts can usually be regained by reconfiguring MFA or working with support.

Use these steps depending on what still works:

1. If sign-in still works somewhere (PC/browser)
   • Sign in to the affected account in a browser.
   • Go to the security/MFA management page for that account:
     • For Microsoft 365 work/school, open the Additional security verification page or Security info page (for example via office.com → account manager → View account → Update info).
   • Remove the old phone/Auth method:
     • Delete the old phone entry or old Authenticator registration.
   • Add the new phone:
     • Choose Add sign-in method → Phone and enter the new number, or re-add Microsoft Authenticator and follow the prompts on the new device.
2. If Microsoft Authenticator backup was enabled on the old phone (same platform)
   • Install Microsoft Authenticator on the new phone.
   • Sign into the same backup account (iCloud for iOS) and restore the backup as described in the Authenticator backup article. This restores backed-up accounts, but work/school and passwordless accounts will still require signing in again.
3. If completely locked out and this is a work/school (tenant) account
   • Another admin in the organization can reset MFA for the account so it can be set up again on the new phone.
   • If there is only one global admin and that admin is locked out, Microsoft’s Data Protection team must assist. Open or request a support ticket via Microsoft support (phone or via a partner/new temporary tenant) and ask for a Data Protection/MFA reset for the tenant admin, as described in the Q&A examples.
4. If this is a personal Microsoft account and no method works
   • Use the account recovery options on the Microsoft account security page to prove identity and then remove the old Authenticator device from the two-step verification area, and add the new phone/Auth method.

Going forward, enable backup in Microsoft Authenticator (and, for work/school, add at least one extra sign-in method such as SMS or another phone) so a future phone change does not cause lockout.

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References:

• Use a screen reader to set up and troubleshoot multifactor authentication
• Back up your accounts in Microsoft Authenticator
• Microsoft Authenticator FAQs
• Troubleshoot signing in with a passkey
• How Do I Regain Access to My Account After Losing Access to Microsoft Authenticator? (Urgent Request). - Microsoft Q&A
• Cannot authenticate with E-mail when logging into Microsoft Authenticator(iOS). - 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
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A
• Severity A Situation - Locked out of global admin account (MFA) - business down - Microsoft Q&A