A couple of days ago my mail server stopped working and all I'm getting is this postfix error message: muttley postfix/smtpd[2718]: NOQUEUE: reject: MAIL from localhost.localdomain[127.0.0.1]: 452 4.3.1 Insufficient system storage; proto=SMTP helo=<notify.ossec.net> muttley postfix/smtpd[2718]: warning: not enough free space in mail queue: 17719296 bytes < 1.5*message size limit So I upped the limits of my postfix config settings to: postconf -e "mailbox_size_limit = 1048576000" postconf -e "message_size_limit = 30720000" But still no joy. Then I had a look at my free diskspace: root@muttley:/# df Filesystem           1K-blocks      Used Available Use% Mounted on /dev/xvda             10321208   9781896     15024 100% / none                    293304       116    293188   1% /dev none                    297888         0    297888   0% /dev/shm none                    297888        72    297816   1% /var/run none                    297888         0    297888   0% /var/lock none                    297888         0    297888   0% /lib/init/rw none                  10321208   9781896     15024 100% /var/lib/ureadahead/debugfs root@muttley:/# df -i Filesystem            Inodes   IUsed   IFree IUse% Mounted on /dev/xvda             655360  407790  247570   63% / none                   73326     498   72828    1% /dev none                   74472       1   74471    1% /dev/shm none                   74472      43   74429    1% /var/run none                   74472       3   74469    1% /var/lock none                   74472       1   74471    1% /lib/init/rw none                  655360  407790  247570   63% /var/lib/ureadahead/debugfs Apparently this is a known bug with ureadahead but I haven't been able to find anyone else mention that it was affecting postfix: https://bugs.launchpad.net/ubuntu/+source/ureadahead/+bug/501715 Anyway I installed the fix (https://launchpad.net/ubuntu/+source/ureadahead) but I'm still getting the same errors. Is this the root of the problem do you think or is it something else? Can anyone help me out with this it's driving me nuts?! Cheers, Andrew Full postfix settings printed below for reference: //root@muttley:~# postconf -n alias_database = hash:/etc/aliases alias_maps = hash:/etc/aliases append_dot_mydomain = no biff = no broken_sasl_auth_clients = yes config_directory = /etc/postfix html_directory = /usr/share/doc/postfix/html mailbox_size_limit = 1048576000 message_size_limit = 30720000 mydestination = muttley.vps.bitfolk.com, localhost, localhost.localdomain myhostname = muttley.vps.bitfolk.com mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 myorigin = /etc/mailname proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps $recipient_canonical_maps $relocated_maps $transport_maps $mynetworks $virtual_mailbox_limit_maps queue_minfree = 0 readme_directory = /usr/share/doc/postfix recipient_delimiter = + smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) smtpd_delay_reject = yes smtpd_error_sleep_time = 4h smtpd_hard_error_limit = 20 smtpd_helo_required = yes smtpd_helo_restrictions = permit_mynetworks,    reject_invalid_hostname,    permit smtpd_recipient_restrictions = permit_mynetworks,    permit_sasl_authenticated,    reject_unauth_destination,    reject_non_fqdn_recipient,    reject_unknown_recipient_domain,    reject_rbl_client sbl.spamhaus.org,    permit smtpd_sasl_auth_enable = yes smtpd_sasl_authenticated_header = yes smtpd_sasl_path = private/auth smtpd_sasl_type = dovecot smtpd_sender_restrictions = permit_sasl_authenticated,    permit_mynetworks,    reject_non_fqdn_sender,    reject_unknown_sender_domain,    permit smtpd_soft_error_limit = 10 smtpd_tls_cert_file = /etc/postfix/smtpd.cert smtpd_tls_key_file = /etc/postfix/smtpd.key smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache smtpd_use_tls = yes virtual_alias_domains = virtual_alias_maps = proxy:mysql:/etc/postfix/mysql-virtual_forwardings.cf, mysql:/etc/postfix/mysql-virtual_email2email.cf virtual_gid_maps = static:5000 virtual_mailbox_base = /home/vmail virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql-virtual_domains.cf virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql-virtual_mailboxes.cf virtual_transport = dovecot virtual_uid_maps = static:5000