Any suggestions to help me troubleshoot a "killed by signal 11" problem with Postfix? I've Googled and fiddled, but cannot figure it out. I have no idea where to look/start. Based on this post, Wietse suggests this type of problem happens when there compiled with different libraries. I tried ldd on various programs and found they all seemed to line up, but I know little. http://www.security-express.com/archives/postfix/2005-12/0152.html Logs: [root at srv log]# grep 'killed by signal 11' maillog* maillog:Aug 19 13:50:21 srv postfix/master[2719]: warning: process /usr/libexec/postfix/smtpd pid 3996 killed by signal 11 maillog.1:Aug 12 07:01:18 srv postfix/master[20954]: warning: process /usr/libexec/postfix/local pid 25006 killed by signal 11 maillog.1:Aug 13 06:22:38 srv postfix/master[25310]: warning: process /usr/libexec/postfix/cleanup pid 1195 killed by signal 11 maillog.1:Aug 13 18:02:37 srv postfix/master[25310]: warning: process /usr/libexec/postfix/pipe pid 6419 killed by signal 11 maillog.1:Aug 14 07:37:41 srv postfix/master[11557]: warning: process /usr/libexec/postfix/smtp pid 12580 killed by signal 11 maillog.1:Aug 16 14:18:04 srv postfix/master[11557]: warning: process /usr/libexec/postfix/smtpd pid 5323 killed by signal 11 maillog.1:Aug 17 02:37:19 srv postfix/master[11557]: warning: process /usr/libexec/postfix/anvil pid 9575 killed by signal 11 maillog.1:Aug 18 03:02:46 srv postfix/master[11909]: warning: process /usr/libexec/postfix/proxymap pid 19937 killed by signal 11 maillog.1:Aug 19 03:38:28 srv postfix/master[22278]: warning: process /usr/libexec/postfix/proxymap pid 28403 killed by signal 11 maillog.2:Aug 6 07:13:42 srv postfix/master[20954]: warning: process /usr/libexec/postfix/cleanup pid 26753 killed by signal 11 maillog.2:Aug 6 17:45:42 srv postfix/master[20954]: warning: process /usr/libexec/postfix/smtpd pid 31635 killed by signal 11 maillog.3:Jul 31 22:40:54 srv postfix/master[20149]: warning: process /usr/libexec/postfix/smtpd pid 21654 killed by signal 11 maillog.3:Aug 3 00:57:53 srv postfix/master[20149]: warning: process /usr/libexec/postfix/cleanup pid 10409 killed by signal 11 maillog.4:Jul 28 03:37:04 srv postfix/master[3457]: warning: process /usr/libexec/postfix/cleanup pid 14690 killed by signal 11 maillog.4:Jul 28 09:05:51 srv postfix/master[17435]: warning: process /usr/libexec/postfix/smtp pid 17490 killed by signal 11 System: CentOS 5.0 - updated postfix-pflogsumm-2.3.3-2.el5.centos.mysql_pgsql postfix-2.3.3-2.el5.centos.mysql_pgsql pam_mysql-0.6.2-4 cyrus-sasl-plain-2.1.22-4 cyrus-sasl-2.1.22-4 cyrus-sasl-md5-2.1.22-4 cyrus-sasl-sql-2.1.22-4 cyrus-imapd-utils-2.3.8-9 cyrus-imapd-devel-2.3.8-9 cyrus-sasl-lib-2.1.22-4 cyrus-sasl-devel-2.1.22-4 cyrus-sasl-gssapi-2.1.22-4 cyrus-imapd-perl-2.3.8-9 cyrus-imapd-2.3.8-9 sqlgrey-1.7.6-1 clamav-db-0.91.1-1.el5.rf amavisd-new-2.5.2-1.el5.rf clamav-0.91.1-1.el5.rf mysql-5.0.22-2.1 mysql-server-5.0.22-2.1 mysql-devel-5.0.22-2.1 -- Sincerely, John Thomas