I tried to configure my account on zimbra server installed on my dedicated server.

It is giving error on sending email yesy. I tried it with SSL port 465, SSL port 25, and without SSL port 25 but it still gives error. Any suggestions?

"Send test e-mail message: Outlook cannot connect to your outgoing (SMTP) e-mail server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP)."

pop3 = mail.bpo-network.com port 995
smtp = mail.bpo-network.com port 25 / 465