Since my ISP blocks outgoing packets on port 25, I need to relay my mail through their servers. My ISP requires secure authentication and doesn't support SSL. Based on my configuration, this is what happens:   esmtproutes config file (forward all mail to isp) => ": <isp_mail_hostname>" esmtpauthclient => "<isp_mail_hostname> <user> <password>"   With this setup, courier log reports: "server courieresmtp: Crashed child process 6337, while delivering to hotmail.com" when I send a test message (in this case to hotmail). How can I find out more about what caused the child process to crash? BTW, the hostname is resolved, so there's no DNS issues.

On another note, while my ISP does not support SSL, if I force it with the security option in the esmtproutes file, I at least get an error back from the ISP stating: "500 unable to set minimum security level". So it seems at least with SSL I get a result with the SMTP servers.