I've installed ssmtp on Centos 6 and configured it, here is my ssmtp.conf file contain :

[email protected] mailhub=smtp.gmail.com:587 rewriteDomain=gmail.com [email protected] UseTLS=Yes UseSTARTTLS=Yes [email protected] AuthPass=Mail00Test FromLineOverride=YES TLS_CA_FILE=/etc/pki/tls/certs/ca-bundle.crt

When sending mails, this error displays :

CANNOT OPEN SMTP.GMAIL.COM:587