A Microsoft app for iOS and Android devices that enables authentication with two-factor verification, phone sign-in, and code generation
For a personal Microsoft account created with live.com, update the sign-in alias and security methods separately:
- Go to Manage how you sign in to Microsoft at https://account.live.com/names/manage.
- Select Add email or Add phone number to add a new alias.
- If needed, select Make primary for the new alias.
- Remove the old email address or phone number only after the new alias is added. A primary alias cannot be removed until another email or phone number exists on the account.
If the issue is that verification codes are still going to the old phone number and sign-in cannot be completed:
- On the sign-in screen, select I don't have any of these.
- Follow the prompts to update backup security info.
- If prompted to verify or add new security info, complete that process. Do not change all security info at the same time, because the account may be restricted for 30 days.
If Microsoft Authenticator is being moved to a new phone:
- Keep the old phone until sign-in works on the new phone.
- On Android, open Microsoft Authenticator > Settings > turn on Cloud Backup.
- On iPhone, enable iCloud Drive, iCloud Keychain, iCloud Backup, and turn on Authenticator under Apple Account > iCloud > Saved to iCloud.
- Restore Authenticator on the new phone.
- For work or school accounts restored to a new phone, sign in again to complete setup.
If the account is a work or school account instead of a personal live.com account:
- Go to the Additional security verification page or the Security info page from office.com.
- Delete the old phone entry.
- Select Add sign-in method.
- Choose Phone and enter the new number.
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