Пример конфигурации для  Postfix 2.1.x, позволяющей ограничить доступ  писем с
определенными атачами,
с генерацией отчета о недоставке отправителю,  c указанием причины блокировки.

main.cf: 

   mydomain = test.ru
   myorigin = $mydomain
   soft_bounce = no
   bounce_size_limit = 50000
   relayhost = mail.test.ru
   queue_directory = /var/spool/postfix
   command_directory = /usr/local/sbin
   daemon_directory = /usr/local/libexec/postfix
   mail_owner = fcmail
   default_privs = nobody
   mynetworks_style = subnet
   mynetworks = 192.168.0.0/16
   alias_maps = hash:/etc/mail/aliases
   alias_database = hash:/etc/mail/aliases
   mail_spool_directory = /var/mail
   smtp_always_send_ehlo = yes
   transport_maps = hash:/usr/local/etc/postfix/transport
   smtpd_helo_required = yes
   message_size_limit = 5242880
   readme_directory = no
   sample_directory = /usr/local/etc/postfix
   sendmail_path = /usr/local/sbin/sendmail
   setgid_group = maildrop
   manpage_directory = /usr/local/man
   newaliases_path = /usr/local/bin/newaliases
   mailq_path = /usr/local/bin/mailq
   local_recipient_maps = $alias_maps unix:passwd.byname
   notify_classes = delay, protocol, resource, software, policy
   header_checks=regexp:/usr/local/etc/postfix/header_checks
   header_checks=pcre:/usr/local/etc/postfix/header_checks
   mime_header_checks=regexp:/usr/local/etc/postfix/mime_checks
   mime_header_checks=pcre:/usr/local/etc/postfix/mime_checks
   default_process_limit=500
   smtpd_sender_restrictions = check_sender_access
   hash:/usr/local/etc/postfix/smtpd.sender, permit
   relocated_maps=hash:/usr/local/etc/postfix/relocated
   maximal_queue_lifetime = 1h
   delay_warning_time = 1h
   bounce_notice_recipient = it
   2bounce_notice_recipient = it
   error_notice_recipient = it
   smtp_skip_4xx_greeting = yes
   smtp_skip_5xx_greeting = no
   access_map_reject_code = 550
   reject_code = 550
   unknown_client_reject_code = 550

Правила фильтрации в файле mime_checks:

   /^\s*Content-(Disposition|Type).*name\s*=\s*"?(.+\.(lnk|asd|hlp|ocx|reg\
      |bat|c[ho]m|cmd|exe|dll|vxd|pif|scr|hta|jse?|sh[mbs]|vb[esx]|ws[fh]\
      |wav|mov|wmf|xl|jpg|bmp|gif|mp3))"?\s*$/ \
      REJECT 550 Attachment type not allowed. File "$2" has unacceptable extension "$3"

Для дублирования уведомлений на служебный адрес, нужно указать:
       bounce_notice_recipient = it
       2bounce_notice_recipient = it
       error_notice_recipient = it
   где it - Ваше е-mail или группа рассылки.