Postfix - set up Help

hi, having big problem with postfix. Server behind firewall

Router = 192.168.0.1
Mail server = 192.168.0.200

Static Ip = XXX.XX.XX
MX records looked up and look ok.

Can't get this to work,

#mynetworks_style = host
delay_warning_time = 4h
smtpd_banner = $myhostname ESMTP $mail_name ($mail_version) (Mandrake Linux)
unknown_local_recipient_reject_code = 450
#smtp-filter_destination_concurrency_limit = 2
#lmtp-filter_destination_concurrency_limit = 2
#smtpd_sasl_path = /etc/postfix/sasl:/usr/lib/sasl2
#recipient_delimiter = +
smtpd_recipient_restrictions = permit_mynetworks, reject_unauth_destination
owner_request_special = no
alias_maps = hash:/etc/postfix/aliases
alias_database = hash:/etc/postfix/aliases
virtual_maps = hash:/etc/postfix/virtual
canonical_maps = hash:/etc/postfix/canonical
#inet_interfaces = $myhostname
proxy_interfaces = XX.XX.XX
transport_maps = hash:/etc/postfix/transport
mydestination = $myhostname localhost.$mydomain
ignore_mx_lookup_error = yes
relayhost = "mail.myhostname"

Mail returns "Host or domain name not found. Name service error for name=XXX.XX type=A: Host not found, try again"

Any help ?? Please

It was my ISP jerking me around. made couple calls, they stop
blocking ports Bang - Its up