Look like your sendmail don't accept connection at all...
Try this to create new sendmail.cf...
- have sendmail.cf installed
- vi /etc/mail/sendmail.mc
- by default sendmail only listen to 127.0.0.1, so comment it as
dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
- use m4 to generate new sendmail.cf
# m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
note: This will overwrite existing sendmail.cf, if needed do a backup
- restart sendmail, check with to, it shd show sendmail accepting connection
# ps -ef|grep -i sendmail
- telnet to port 25 to try also...
- test mail...
# mail -s "Testing"
youremailaddress@abc.com
If still not work, do you have any firewall blocking port 25?
Hope this will help...