Mail server postfix mail considered junk

i'm having a small problem with correctly se开发者_开发百科tting my postfix server as to not be regarded as a spam server.

There should be some switches and simple configuration to do that, but i cannot find that. Can anybody point to an online resources that indicated on how to whitelist my server ?

Thanks for recommending our DNS tools, we would like to echo what Gryphius stated about having correct DNS records for MX, PTR and SMTP Banner. If any of these are incorrect it can result in major mail problems. If your PTR and SMTP Banner do not match or resolve to the same FQDN most major ISPs will either mark your message as spam or disallow the message completely.

hard to tell without an actual domain name or server IP

in most cases, the MTA configuration is not the cause of messages being detected as spam (the postfix default configuration does a very good job of making sure your server does not backscatter, is not an open relay etc.) one important configuration value is your HELO string, it should contain your fully qualified public hostname and match the A record of that server. forged or not fully qualified HELO's can cause mail rejects.

apart from that, your problem probably lies in your DNS configuration(A record/rDNS does not match, no MX record, invalid SPF records, ....) or you might have a "dirty" IP address (not static/marked as consumer dial-up ip/blacklisted/....). use the tools at http://mxtoolbox.com to check this.