log/messages: Mar 6 21:06:22 ns310931 postfix/smtpd[20879]: sql_select option missing Mar 6 21:06:22 ns310931 postfix/smtpd[20879]: auxpropfunc error no mechanism available log/maillog: cat maillog | grep "21:06:22" no error i don't know why postfix sends this error, i don't see any reason on the logs!
thanks till Solution: http://www.cyberciti.biz/faq/postfix-sql_select-option-missing-auxpropfunc-error/ PROBLEM SOLVED!