I'm trying to configure the relay , I follow this link http://wiki.zimbra.com/index.php?title=Outgoing_SMTP_Authentication but when I try to send it gave

SASL authentication failed; server mail.domain.com[xx.xx.xx.xx] said: 535 Incorrect authentication

I tried to configure the Microsoft outlook in order to see if the problem from the cpanel but the same except I enabled the SMTP tab use same username and password "Server needs authentication" in my email client

Any body help would be appreciated.