diff --git a/dapostinstall.sh b/dapostinstall.sh
index ed7d373..1996fa8 100644
--- a/dapostinstall.sh
+++ b/dapostinstall.sh
@@ -229,6 +229,12 @@ cp dns_a.conf custom/
 cd custom
 perl -pi -e "s/^smtp=\\|IP\\|\n/smtp=\\|IP\\|\n/poczta=\\|IP\\|\n/" dns_a.conf
 
+echo "Instalacja bezpiecznego DMARC"
+
+cd /usr/local/directadmin/data/templates/custom
+cp ../dns_txt.conf .
+echo '_dmarc="v=DMARC1;p=quarantine;pct=100;sp=none;fo=0:d:s;aspf=s;adkim=r;"' >> dns_txt.conf
+
 echo "Inne optymalizacje"
 
 cd $DAPOSTINSTALL_DIR