Outlook 98 has problems posting messages
Outlook 98 is unable to post messages via SMTP
Outlook 98 does not support multi-line SMTP headers and will fail to post messages if the server returns any.
If you are using multi-line SMTP responses such as SMTPLogonMes then you will need to disable them to allow Outlook 98 to post messages through the SMTP server.
This problem does not affect version 5 onwards.
Keywords:Outlook SMTP posting headers multi-line