Outlook: The Message Could Not Be Sent - An Error Has Occurred

Email | Updated 2026
Quick Answer

This generic send error usually means your outgoing (SMTP) server settings are incorrect. Set the outgoing server to mail.yourdomain.com, port 465 with SSL, and enable SMTP authentication using your full email address and password.

For complete Outlook troubleshooting steps and all error codes, see our full guide:

Common Outlook Email Errors

Correct Email Settings

Most Outlook errors are caused by incorrect server settings. Use these values:

  • Incoming/Outgoing Server - mail.yourdomain.com
  • POP3 Port - 995 (SSL) or IMAP Port - 993 (SSL)
  • SMTP Port - 465 (SSL)
  • Username - your full email address
  • Authentication - enabled for outgoing, SPA disabled

For step-by-step setup: How to Set Up Email in Microsoft Outlook

This article has been consolidated into our Common Outlook Email Errors guide for easier reference.

  • 420 Users Found This Useful

Was this answer helpful?

Related Articles

Outlook: The host yourdomain could not be found - Socket Error: 11001

Email | Updated 2026 Quick Answer Socket Error 11001 means Outlook cannot resolve the...

Outlook: Unable to logon to the server using Secure Password Authentication

Email | Updated 2026 Quick Answer This error occurs when 'Log on using Secure Password...

What are my mail server names?

Email & Webmail | Updated 2026 When setting up email in Outlook, Thunderbird, your phone,...

How Do I Change My MX Records

Email & Webmail | Updated March 2026 MX records control where email for your domain is...

How do I block emails containing zip attachments

Email & Webmail | Updated 2026 If you are receiving spam or phishing emails with .zip...



Save 30% on web hosting - Use coupon code Hosting30