diff --git a/data/Dockerfiles/postfix/postfix.sh b/data/Dockerfiles/postfix/postfix.sh
index 8ffb76f6a..2960444cb 100755
--- a/data/Dockerfiles/postfix/postfix.sh
+++ b/data/Dockerfiles/postfix/postfix.sh
@@ -395,7 +395,7 @@ EOF
 
 if [ ! -f /opt/postfix/conf/dns_blocklists.cf ]; then
   cat <<EOF > /opt/postfix/conf/dns_blocklists.cf
-# This file can be edited. 
+# This file can be edited.
 # Delete this file and restart postfix container to revert any changes.
 postscreen_dnsbl_sites = wl.mailspike.net=127.0.0.[18;19;20]*-2
   hostkarma.junkemailfilter.com=127.0.0.1*-2
@@ -403,7 +403,6 @@ postscreen_dnsbl_sites = wl.mailspike.net=127.0.0.[18;19;20]*-2
   list.dnswl.org=127.0.[0..255].1*-4
   list.dnswl.org=127.0.[0..255].2*-6
   list.dnswl.org=127.0.[0..255].3*-8
-  ix.dnsbl.manitu.net*2
   bl.spamcop.net*2
   bl.suomispam.net*2
   hostkarma.junkemailfilter.com=127.0.0.2*3
@@ -419,6 +418,9 @@ EOF
 fi
 DNSBL_CONFIG=$(grep -v '^#' /opt/postfix/conf/dns_blocklists.cf | grep '\S')
 
+# Remove discontinued Nixspam DNSBL from existing dns_blocklists.cf
+sed -i '/ix\.dnsbl\.manitu\.net\*2/d' /opt/postfix/conf/dns_blocklists.cf
+
 if [ ! -z "$DNSBL_CONFIG" ]; then
   echo -e "\e[33mChecking if ASN for your IP is listed for Spamhaus Bad ASN List...\e[0m"
   if [ -n "$SPAMHAUS_DQS_KEY" ]; then
diff --git a/docker-compose.yml b/docker-compose.yml
index cd85304b4..a11e02d1a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -316,7 +316,7 @@ services:
             - dovecot
 
     postfix-mailcow:
-      image: mailcow/postfix:1.78
+      image: mailcow/postfix:1.79
       depends_on:
         mysql-mailcow:
           condition: service_started