I have Vesta Control Panel on my Ubuntu 13.04 x32. When sending emails is launched the following error in the log ( /var/log/exim4/mainlog): 2014-04-08 11:41:59 1WW4bC-0008Om-0I == nxxx@gmail.com R=dnslookup T=remote_smtp defer (101): Network is unreachable 2014-04-08 11:41:59 1WWpOH-0004fL-2R == bounce-mc.us3_24286051.272073-nxxx=aeroboteco.com.br@mail21.wdc03.rsgsv.net R=dnslookup T=remote_smtp defer (-53): retry time not reached for any host The command: telnet alt1.gmail-smtp-in.l.google.com 25 returns: Trying 173.194.66.27... Trying 2a00:1450:400c:c03::1a... telnet: Unable to connect to remote host: Network is unreachable