diff --git a/dms-lxc.sh b/dms-lxc.sh
index 33da631..77f07cc 100644
--- a/dms-lxc.sh
+++ b/dms-lxc.sh
@@ -279,6 +279,10 @@ msg_info "Installiere Updates & Docker im Container ..."
 pct exec "$CTID" -- bash -c '
   set -e
   export DEBIAN_FRONTEND=noninteractive
+  # Debian-Templates bringen oft Postfix/Exim mit -> belegt Port 25 und bricht
+  # den Mailserver-Container (Port-Bind + Netzwerk-Setup). Daher entfernen.
+  systemctl disable --now postfix exim4 >/dev/null 2>&1 || true
+  apt-get purge -y -qq postfix "exim4*" >/dev/null 2>&1 || true
   apt-get update -qq
   apt-get install -y -qq ca-certificates curl gnupg openssl jq >/dev/null
   install -m 0755 -d /etc/apt/keyrings