Using Classic Outlook on Windows for personal email, calendar, and contact management
I’m sorry to hear that your Hotmail account may have been compromised and that your outgoing messages are being rejected as spam.
Please try the following:
- Run a full antivirus or malware scan on the device you use to access the account.
- Sign in to your Microsoft account and review Recent activity. Mark any unfamiliar activity as not yours.
- Check your account settings and remove any unfamiliar aliases, recovery details, connected accounts, forwarding addresses, inbox rules, or automatic replies.
- Since you have already changed your password, enable two-step verification to help secure the account.
- Use the Microsoft Sign-in Helper to complete any required security verification and unblock the account:
- After completing the security checks, send one simple test email from Outlook.com in a web browser without links or attachments.
If the message is still returned, please reply with the complete undeliverable notice, including the error code, while removing your email address and any other personal information. This will help identify whether the rejection is caused by an account restriction or another delivery issue.
Please feel free to let me know if you have any further updates, thanks.
If the answer is helpful, please click "Yes". If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.