Use the Microsoft Sign-in Helper first. It checks the account and guides the next recovery steps: Sign-in Helper
If the account was compromised, follow this sequence:
- Scan the PC for malware before changing the password
- Open Windows Security.
- Go to Virus and threat protection.
- Select Scan options > Full scan > Scan now.
- This is important before any password change so malware does not capture the new password.
- Try to reset the password
- If sign-in is still possible, use Change password.
- If sign-in is not possible, use Recover your account and enter the email address, phone number, or Skype name tied to the account.
- Make sure the account name is entered correctly, including the correct domain such as
.comor.co.uk. - If one alias is not recognized, try another email alias or phone number previously added to the account.
- If verification codes are not arriving
- Continue through the Sign-in Helper, because it is the main path Microsoft provides for sign-in and verification problems.
- If the account remains blocked, use the Outlook.com unblock flow: Sign-in Helper
- If the account is hacked and recovery options no longer work
- Use the hacked account recovery guidance: Start
- If the recovery email or phone no longer works, the helper can either provide self-help steps or offer the chance to talk to an agent.
- Important limitation
- If two-step verification is turned on and none of the alternate verification methods are accessible, support agents cannot send password reset links or change account details.
- After access is restored
- Check account settings such as connected accounts, forwarding, and automatic replies, because these may have been changed during the compromise.
References: