Hi Guys My current box is a centos 5.3 running amavisd, postifx 2.2.8, l since last week we cannot longer send mail to gmail cause we do not have domin authentication, DKIM, our version of postfix and server has been stable for more than 10 years, we have configured correctly SPF, DMARC and all need to send and rececive mail but we a re missing DKIM mail-tester.com return 9 of 10 OK - with -1 on DKIM Question? I have read that i need postfix Postfix 2.3.3 or better currently working. or higher? since dkim.milter dos not run o was not included on postfix prior to that version How do I upgrade my postfix on centos 5.3 to version 3.3.0 or higher without hunging my server? I would appreciate any help.