Sending, receiving, and organizing email in Outlook.com
Hello, and thank you for reaching out to Microsoft Q&A.
Is he experiencing the same issue when signing in on a different device or web browser?
Please try this:
- Open an incognito/private browsing tab in your current browser, then sign in with his account at https://account.microsoft.com/ and request the verification code.
- See whether he can sign in successfully.
If he gets the same error in a private browsing tab, avoid making repeated sign-in attempts. Wait 24 hours and try again, as this may reset any temporary lock.
Alternatively, try resetting his Microsoft account password once and then see whether he can sign in.
If he is still having issues signing in, let me know, and we can try the account recovery options next.