kein Versand von Mails möglich

[mail at nicofunke.name]

     Hallo zusammen,

     ich beschäftige mich aktuell wieder mit Postfix / Dovecot und  
finde mein Fehler nicht.

     Zum Setup nutze ich ein aktuelles Debian mit Postfix aus den  
Standard Paketquellen und Dovecot in der aktuellen Version direkt aus  
deren Paketquellen.

     Ich kann mich in Dovecot einloggen, habe meine Mails migriert und  
kann im Ordnersystem problemlos arbeiten.
     Die Mails werden auch korrekt zugestellt.

     Jedoch kann ich nicht senden. Ich bekomme vom Mailclient  
(Thunderbird) folgende Meldung:
     Sender address rejected: not owned by user

     In den Postfix Logs steht folgendes:
     postfix/smtpd[1502845]: NOQUEUE: reject: RCPT from unknown 553  
5.7.1 Sender address rejected: not owned by user

     Die Postfixkonfiguration ist noch ziemlich einfach, jedoch finde  
ich nicht was falsch ist.
     Es geht auch erst mal nicht um Systemmails oder ähnliches.

     Sieht jemand mein Fehler?

     postconf -n:

     alias_database = hash:/etc/aliases
     alias_maps = hash:/etc/aliases
     biff = no
     broken_sasl_auth_clients = yes
     compatibility_level = 3.9
     debug_peer_level = 2
     disable_vrfy_command = yes
     inet_interfaces = all
     inet_protocols = ipv4
     local_recipient_maps = $virtual_mailbox_maps
     local_transport = virtual
     mailbox_command =
     mailbox_size_limit = 0
     message_size_limit = 30240000
     mydestination = $myhostname, blocxx.org, xhc01.blocxx.org,  
localhost.blocxx.org, localhost
     myhostname = xhc01.blocxx.org
     mynetworks = 127.0.0.0/8
     mynetworks_style = host
     myorigin = /etc/mailname
     recipient_delimiter = +
     relay_domains = hash:/etc/postfix/relay_domains
     relayhost =
     smtp_helo_name = mail.blocxx.org
     smtp_tls_CAfile = /etc/ssl/blocxx/intermediate.crt
     smtp_tls_CApath = /etc/ssl/certs
     smtp_tls_cert_file = /etc/ssl/blocxx/certificate.crt
     smtp_tls_ciphers = high
     smtp_tls_key_file = /etc/ssl/blocxx/blocxx.key
     smtp_tls_loglevel = 1
     smtp_tls_mandatory_ciphers = high
     smtp_tls_mandatory_protocols = >=TLSv1.2
     smtp_tls_protocols = >=TLSv1.2
     smtp_tls_security_level = encrypt
     smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
     smtpd_banner = $myhostname ESMTP $mail_name (Debian)
     smtpd_recipient_restrictions = check_recipient_access  
hash:/etc/postfix/check_recipient_access_rfc,  
permit_sasl_authenticated, permit_mynetworks,  
reject_unverified_recipient, permit
     smtpd_relay_restrictions = permit_mynetworks,  
permit_sasl_authenticated, defer_unauth_destination
     smtpd_sasl_auth_enable = yes
     smtpd_sasl_path = private/auth
     smtpd_sasl_security_options = noanonymous, noplaintext
     smtpd_sasl_tls_security_options = noanonymous
     smtpd_sasl_type = dovecot
     smtpd_tls_CAfile = /etc/ssl/blocxx/intermediate.crt
     smtpd_tls_CApath = /etc/ssl/certs
     smtpd_tls_auth_only = yes
     smtpd_tls_cert_file = /etc/ssl/blocxx/certificate.crt
     smtpd_tls_ciphers = high
     smtpd_tls_key_file = /etc/ssl/blocxx/blocxx.key
     smtpd_tls_mandatory_ciphers = high
     smtpd_tls_mandatory_protocols = >=TLSv1.2
     smtpd_tls_protocols = >=TLSv1.2
     smtpd_tls_received_header = yes
     smtpd_tls_security_level = may
     tls_high_cipherlist = EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH
     tls_preempt_cipherlist = yes
     transport_maps = hash:/etc/postfix/transport, $relay_domains
     virtual_alias_maps = hash:/etc/postfix/virtual
     virtual_transport = lmtp:unix:private/dovecot-lmtp


     Danke für's schauen.

     Best,