rhn-ssl-cert-check cron returns "rhn-ssl-cert-check can't read e-mail address"

Issue

• /etc/cron.daily/rhn-ssl-cert-check returns error message:

  Unable to read the admin e-mail address in /etc/rhn/rhn.conf
  To disable monitoring, add CHECK=no in /etc/sysconfig/rhn/rhn-ssl-cert-check Otherwise, you will have to add a valid email address to receive expiration notifications, 
  either in /etc/rhn/rhn.conf (traceback_mail) or set ADMIN in /etc/sysconfig/rhn/rhn-ssl-cert-check