Unauthorized login attempts

Changing the primary email is not enough: for a personal Microsoft account, disable sign-in permission for the old alias while retaining it for email.

Block the old address from sign-in

Microsoft account aliases share the same account and password, and all aliases are allowed to sign in by default. Making a different alias primary does not automatically block the old one.^1^

1. Sign in directly at account.microsoft.com.
2. Select Your info.
3. Select Sign-in preferences.
4. Ensure the new, private alias is enabled for sign-in.
5. Clear the sign-in checkbox for the old email address that is receiving the unwanted requests.
6. Select Save.
7. Sign out and verify that the new alias works.

Keep the old address as an alias if you still use its mailbox—blocking it from sign-in does not remove it from the account. Do not delete an Outlook.com, Hotmail.com, or Live.com alias merely to stop these attempts; removing a Microsoft-domain alias permanently deletes that address, and it cannot be reclaimed.^2^

Keep the new sign-in alias private and do not use it for public registrations. Attempts made with the old address should then receive a “username has been turned off” response rather than reaching your account.^3^

Treat prompts and reset-code emails separately

• Authenticator approval requests: Continue denying them. Never approve a request you did not initiate.
• Password-reset codes: Do not enter, forward, or reply with them. An unsolicited code can mean that someone entered your address while attempting account recovery; without the code, they cannot complete that verification step.^4^
• Do not use links in unexpected messages. Open the Microsoft account site directly in the browser. Genuine Microsoft account notifications use the @accountprotection.microsoft.com domain, but an authentic message can still have been triggered by somebody else.^5^

Changing the password again is not the main next step because several password changes have not stopped requests aimed at the known old alias.

Check whether anyone actually gained access

1. Open Microsoft account → Security → Review activity.
2. Expand unfamiliar entries and inspect the access type, device, location, and time.
3. Distinguish:
   • Incorrect password entered: Microsoft rejected the attempt.
   • Additional verification requested: a code or Authenticator challenge was triggered.
   • Successful sign-in or an unrecognized profile/security change: possible account access.
4. For unfamiliar entries in Unusual activity, select This wasn't me. For suspicious entries under Recent activity, select Secure your account.^6^

Microsoft does not display every event on this page, so a denied Authenticator prompt might not always appear. The important distinction is whether there is an unfamiliar successful sign-in or account change, rather than merely an unsuccessful attempt or additional-verification event.

If you find successful unauthorized access

Since the password has already been changed, invalidate any remaining sessions:

1. Open the Microsoft account Advanced security options.
2. Review the registered verification methods and remove anything unfamiliar.
3. Scroll to Sign out everywhere and select Sign out.

Signing out can take up to 24 hours and affects browsers and apps, but not Xbox consoles.^7^

If this is instead a work or school account, these personal-account alias controls do not apply. Review My Account → Recent Activity and report unrecognized successful sign-ins to the organization’s IT administrator.^8^

References

1. Block an email address from signing in | Microsoft Support
2. Can I change the email address that is connected to my Clipchamp account? | Microsoft Support
3. How to fix "This username has been turned off" error | Microsoft Support
4. Troubleshoot Microsoft verification code issues | Microsoft Support
5. Can I trust email from the Microsoft account team? | Microsoft Support
6. What is the Recent activity page? | Microsoft Support
7. How to sign out of your Microsoft account everywhere | Microsoft Support
8. View your work or school account sign-in activity from My Sign-ins | Microsoft Support