MTA stopped

[Donnie309]

When i check Zimbra's status i get MTA stopped. All others are running. under MTA it says
postfix is not running
saslauthd is not running
zmsaslauthdctl is not running

and when i run postfix start i get this error message:
warning: not owned by root: /opt/zimbra/postfix-2.4.7.5z/conf/main.cf

if i try to chown this file to root then do a postfix start it gets changed back to owned by zimbra automatically. Any help anyone could give me would be much appreciated.
Thank you.

Donnie