Hello group... I am presently working on: Quick And Easy Setup For DomainKeys Using Ubuntu, Postfix And Dkim-Filter This server is running Ubuntu 9.04 and ISPConfig3... The server will not authenticate using DKIM, I have tried emailing to a Yahoo account and using the DKIM tool located at mailradar.com. When I run 'tail -f /var/log/mail.err' I receive the following: Code: Aug 10 20:16:13 giganetwireless dkim-filter[12139]: 2EE11B8C003: no signature data Aug 10 20:16:13 giganetwireless dkim-filter[12139]: D45E6B8C19A: no signature data Aug 10 20:16:28 giganetwireless dkim-filter[12139]: 6DF32B8C003: no signature data Aug 10 20:16:29 giganetwireless dkim-filter[12139]: 7A8ABB8C19A: no signature data Aug 10 20:17:06 giganetwireless dkim-filter[12139]: D5A26B8C003: no signature data Aug 10 20:17:07 giganetwireless dkim-filter[12139]: 61E55B8C19A: no signature data Aug 10 20:23:32 giganetwireless dkim-filter[12139]: D1864B8C003: no signature data Aug 10 20:23:33 giganetwireless dkim-filter[12139]: 1A498B8C19A: no signature data Aug 10 20:24:35 giganetwireless dkim-filter[12139]: 6C810B8C003: no signature data Aug 10 20:24:36 giganetwireless dkim-filter[12139]: 25BEFB8C19A: no signature data Likewise when I try to run '/etc/init.d/dkim-filter restart' I receive: Code: Starting for DKIM verification only dkim-filter: /etc/dkim-filter.conf: configuration error at line 22: unrecognized parameter Below are the contents of '/etc/dkim-filter.conf' Code: # Log to syslog Syslog yes # Required to use local socket with MTAs that access the socket as a non- # privileged user (e.g. Postfix) # UMask 002 # Sign for example.com with key in /etc/mail/dkim.key using # selector '2007' (e.g. 2007._domainkey.example.com) Domain giganetwireless.net KeyFile /var/gnw-dkim-filter/private.key Selector mail #Selector 2007 # Common settings. See dkim-filter.conf(5) for more information. AutoRestart no Background yes Canonicalization simple DNSTimeout 5 Mode sv SignatureAlgorithm rsa-sha256 SubDomains no UseSSPDeny no ASPDiscard no Version rfc4871 Following are the lines added to the base of '/etc/postfix/main.cf' Code: milter_default_action = accept milter_protocol = 2 smtpd_milters = inet:localhost:8891 non_smtpd_milters = inet:localhost:8891 When I view full header information of email received at Yahoo it appears as follows: Code: Authentication-Results: mta571.mail.mud.yahoo.com from=giganetwireless.net; domainkeys=neutral (no sig); from=giganetwireless.net; dkim=neutral (no sig) In ISPConfig3 Firewall I have opened port 8891 TCP & UDP too. What would be the best means of troubleshooting DKIM functionality? Thanking you in advance for your help. Best Regards