E-Mail Virus and Spam Protection

Hi I am Having tremendous problems with spam and viruses

I have installed
clamAV
SpamAssassin
and now MailScanner

I still Cannot get rid of the Spam and viruses

I some how think that the Mailscanner / Spamassassin is not working correctly

I think my error may be in the MailScanner.config setup, I refer to two entries here
Incoming Queue Dir = /var/spool/mqueue ( does not exist )
changed to
Incoming Queue Dir = /var/spool/postfix/incoming

and
Outgoing Queue Dir = /var/spool/mqueue ( does not exist )
changed to
Outgoing Queue Dir = /var/spool/postfix/maildrop

but I am still getting spam / viruses
the tail
tail -f /var/log/mail.log
seems to indicate it is doing something, here is a sample
" Jul 15 10:39:02 jor60-nix01 postfix/qmgr[3386]: 81FF84539C: removed "
but spam /virus are still coming down

Currently I am Using
sudo clamscan -r / --remove
which clears the server but does not last long

Does ANYBODY have any advice ?

Thanks in advance
Andy