Re: Failed to open connection to SMTP server

> Hi Roberto,
> Thank you very much for your message!
> I checked from other computer, the SMTP port 25 is open.
> After I restart sendmail, it could send mail out. Later on
> it stopped again, I need to start sendmail again....
> Hailong

Check your configuration files, it sounds like sendmail is misconfigured.
I could help if you were on qmail or postfix, but nada with sendmail.
Check your firewall and tcp_wrappers rules.
Check your logs, see why the daemon dies.
Can you telnet into the mailserver from the localhost? What about from a
remote host on the same net, or from one outside of your net?