DBERROR: critical database situation

I've just moved my server over to 10.4 from 10.3.9 and in the process am no long able to send or receive mail. I can no long receive emails from outside, or internally. I can connect to the server to send them, but they don't get through to the receiver, whether they are internal or external. It gets queued. If any one can make sense of the log below that would be great. command_directory = /usr/sbin config_directory = /etc/postfix content_filter = daemon_directory = /usr/libexec/postfix debug_peer_level = 2 enable_server_options = yes html_directory = no inet_interfaces = localhost local_recipient_maps = proxy:unix:passwd.byname $alias_maps luser_relay = mail_owner = postfix mailbox_size_limit = 0 mailbox_transport = cyrus mailq_path = /usr/bin/mailq manpage_directory = /usr/share/man message_size_limit = 10485760 mydestination = $myhostname,localhost.$mydomain,newcommunitychurch.org.uk,office.newcommunitychurch.org.uk mydomain_fallback = localhost mynetworks = 127.0.0.1/32,192.168.0.1/24,217.64.120.14/32 mynetworks_style = host newaliases_path = /usr/bin/newaliases queue_directory = /private/var/spool/postfix readme_directory = /usr/share/doc/postfix sample_directory = /usr/share/doc/postfix/examples sendmail_path = /usr/sbin/sendmail setgid_group = postdrop smtpd_pw_server_security_options = plain,login,gssapi smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination,permit smtpd_sasl_auth_enable = yes smtpd_tls_key_file = smtpd_use_pw_server = yes unknown_local_recipient_reject_code = 550 I also have messages in the log like : Dec 12 19:21:44 office pop3[15473]: DBERROR: critical database situation and Dec 12 19:50:29 office postfix/smtpd[25696]: fatal: net/mask pattern 192.168.0.1/24 has a non-null host portion; specify 192.168.0.0/24 if this is really what you want Many, many thanks in advance Justyn