outlook will not send email

Outlook express will not send mail. I can receive it but not send it. I'm totally frustrated. this is the error message I get,

Your server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity. Account: 'mail.comcast.net', Server: 'smtp.comcast.net', Protocol: SMTP, Port: 25, Secure(SSL): No, Socket Error: 10053, Error Number: 0x800CCC0F

Have a look on related topics, already discuss in this forum -

• http://forums.techarena.in/windows-software/1064234.htm
  
• http://forums.techarena.in/windows-x...ort/802106.htm
  
• http://forums.techarena.in/windows-v...ail/791131.htm
  
• http://forums.techarena.in/windows-v...ail/886716.htm

That type of error is often caused by interference from a non-compatible antivirus program. Which antivirus are you running? As a minimum, email scanning in the antivirus must be turned off, although that may not be sufficient to eliminate all bad effects. In a worst case scenario, your antivirus may need to be uninstalled.