Hi, this is my first live installation of a web/mail server and i'm having some problems. I can't post any logs or config files yet because of university firewall blocks ssh, i'll post them as soon as i get home. I've installed CentOS 6 on a server with public ip for a company of a friend. The webmaster intends to host several domains with their mailboxes on this server so i installed ZPanel. The DNS records are managed by the domain registrar. The problem is that i can't send emails from my domain to gmail, yahoo nor hotmail accounts but i am able to send mails to my university email account without problems. maillog shows connection timed out and no route to host errors although it shows the resolved domains and ip's of the servers. First i thought that my ISP was blocking the 25 port because i can't telnet smtp.gmail.com 25 but i got confussed when i was able to telnet my university's mx server I suppose there's some (security?? ) configuration missing for being able to send mail to these known servers that is not required by my university's mail server. I haven't installed amavisd (zpanel's postfix default install) nor setup a spf or dkim record, could be this? Intodns.com tool shows my dns records are fine, including the PTR. The domain/IP is not blacklisted. my ip range is on the PBL list of spamhaus.org that states that is not a blacklist just a range of IP's of broadband/ADSL users (in my case a cable provider). I managed to setup a relayhost through a gmail account but the domain will have several email users and gmail rewrites my relay account address as sender and i don't wan't to create a send rate bottleneck redirecting all the server's domains emails through a single gmail account. thanks in advance for you help.