SYMPTOMS

Sending from an ASP.NET page, SMTP mailing scripts does not work and produces the following error:

**The message could not be sent to the SMTP server. The transport error code
was 0x800ccc15. The server response was not available **

MailEnable SMTP debug log will also display 10053 errors.

CAUSE

McAfee Virus Scan Enterprise 8.0 "Prevent mass mailing worms from sending mail" is blocking port 25

RESOLUTION

Either disable the McAfee Virus Scan Enterprise 8.0 "Prevent mass mailing worms from sending mail" option or exclude port 25 within the scanners properties.