Device Lost for Authentication code - Cannot login

Question

The previous device I used for authentication code was lost, now I cannot login because it requires to enter the authentication code after entering the account and password. There is no other alternative method provided for receiving authentication code. How can I log in?

Answer 1

Because the only verification method is on the lost device, the account’s security info or MFA methods must be reset from outside the normal sign-in flow.

Use the appropriate path based on the type of account:

1. Work or school (Azure AD / Microsoft 365) account
   • If any alternative method was set up (office phone, SMS, security key, etc.), on the MFA prompt choose “Sign in another way” and complete sign-in using that method, then add a new method and remove the old phone.
   • If no other method exists and the lost device was the only factor, contact the organization’s IT/help desk or tenant administrator and request an MFA reset for the account. Admins can clear MFA settings so that registration is required again at next sign-in.
   • If this is the only admin account in the tenant and no one can reset MFA, a Microsoft Data Protection case is required. Open a support request via Microsoft support (phone or a separate tenant, as described in the Q&A references) and ask specifically for the Data Protection team to reset the admin’s authentication methods.
2. Personal Microsoft account (Outlook.com, Hotmail, etc.)
   • If at least one security method (phone/email/app) is still accessible:
     1. Sign in to the Advanced security options page.
     2. Select Add a new way to sign in or verify and configure a new phone/email/app.
     3. After verifying the new method, expand the old (lost) method and select Remove.
   • If all security info is lost but the password is known:
     1. Start sign-in.
     2. At “Verify your identity”, select “I don't have any of these”.
     3. Follow the steps to replace the security info. After replacement, there is a 30‑day wait before normal sign-in is allowed.
   • If the password is also forgotten and no security info is available, complete the Microsoft account recovery form and wait for the review.

During the 30‑day security-info replacement period for personal accounts, if the old security info is recovered, it can still be used to sign in, which cancels the pending change.

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References:

• Use a screen reader to set up and troubleshoot multifactor authentication
• Sign in using two-step verification or security info
• Troubleshoot Microsoft verification code issues
• Common problems with two-step verification for a work or school account
• Cannot log in Outlook. - 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
• Can't sign in to my email - Microsoft Q&A
• How Do I Regain Access to My Account After Losing Access to Microsoft Authenticator? (Urgent Request). - Microsoft Q&A
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A
• What happens if there's an unusual sign-in to your account