Configuration Files

Centos / RHEL / CloudLinux 7 (systemd)

// spamassassin (Anti-spam Settings)
/etc/mail/spamassassin/local.cf 

// spamass-milter (Anti-spam Milter Settings)
/etc/sysconfig/spamass-milter

// clamd scan deamon (Anti-virus Settings)
/etc/clamd.d/scan.conf

// clamav signature update (Anti-virus Signature Settings)
/etc/freshclam.conf

// clamav-milter (Anti-virus Milter Settings)
/etc/mail/clamav-milter.conf

Centos / RHEL / CloudLinux 6 (sysvinit)

// spamassassin (Anti-spam Settings)
/etc/mail/spamassassin/local.cf 

// spamass-milter (Anti-spam Milter Settings)
/etc/sysconfig/spamass-milter

// clamd scan deamon (Anti-virus Settings)
/etc/clamd.conf

// clamav signature update (Anti-virus Signature Settings)
/etc/freshclam.conf

// clamav-milter (Anti-virus Milter Settings)
/etc/clamav-milter.conf

Debian / Ubuntu

// spamassassin (Anti-spam Settings)
/etc/mail/spamassassin/local.cf 

// spamass-milter (Anti-spam Milter Settings)
/etc/default/spamass-milter

// clamd scan deamon (Anti-virus Settings)
/etc/clamav/clamd.conf

// clamav signature update (Anti-virus Signature Settings)
/etc/clamav/freshclam.conf

// clamav-milter (Anti-virus Milter Settings)
/etc/clamav/clamav-milter.conf