diff --git a/install_amavis.sh b/install_amavis.sh
index 5e8079a..d3a3533 100755
--- a/install_amavis.sh
+++ b/install_amavis.sh
@@ -704,7 +704,6 @@ else
 fi
 if ! $DB_IN_USE ; then
    echo -e "[3] \033[37m\033[1mSkip (No Database in use)\033[m"
-   _DB_TYPE="None"
 else
    echo "[3] Skip (No Database in use)"
 fi
@@ -4550,33 +4549,42 @@ fi
 
 if [[ "$DB_TYPE" = "PostgreSQL" ]]; then
 
-   cat >> /etc/amavis/conf.d/50-user <<EOF
+   if [[ -n "${DB_NAME}" ]] && [[ -n "${DB_HOST}" ]] && [[ -n "${DB_USER}" ]] && [[ -n "${DB_PASS}" ]] ; then
+
+      cat >> /etc/amavis/conf.d/50-user <<EOF
 
 ## - lookup for local domains in PostgreSQL database
 ## -
-@lookup_sql_dsn = (
-   ['DBI:Pg:database=${DB_NAME};host=${DB_HOST}', '$DB_USER', '$DB_PASS']
-);
-\$sql_select_policy =  'SELECT \\'Y\\' AS local FROM domain WHERE \\'@\\' || domain IN (%k);';
+#@lookup_sql_dsn = (
+#   ['DBI:Pg:database=${DB_NAME};host=${DB_HOST}', '$DB_USER', '$DB_PASS']
+#);
+#\$sql_select_policy =  'SELECT \\'Y\\' AS local FROM domain WHERE \\'@\\' || domain IN (%k);';
 EOF
-   if [[ "$?" -ne 0 ]] ; then
-      installation_failed=true
-      error "$(cat $tmp_err_msg)"
+      if [[ "$?" -ne 0 ]] ; then
+         installation_failed=true
+         error "$(cat $tmp_err_msg)"
+      fi
+
    fi
 
 elif [[ "$DB_TYPE" = "MySQL" ]];then
-   cat >> /etc/amavis/conf.d/50-user <<EOF
+
+   if [[ -n "${DB_NAME}" ]] && [[ -n "${DB_HOST}" ]] && [[ -n "${DB_USER}" ]] && [[ -n "${DB_PASS}" ]] ; then
+
+      cat >> /etc/amavis/conf.d/50-user <<EOF
 
 ## - lookup for local domains in MySQL database
 ## -
-@lookup_sql_dsn = (
-   ['DBI:mysql:database=${DB_NAME};host=${DB_HOST}', '$DB_USER', '$DB_PASS']
-);
-\$sql_select_policy =  'SELECT "Y" AS local FROM domain WHERE CONCAT("@", domain) IN (%k)';
+#@lookup_sql_dsn = (
+#   ['DBI:mysql:database=${DB_NAME};host=${DB_HOST}', '$DB_USER', '$DB_PASS']
+#);
+#\$sql_select_policy =  'SELECT "Y" AS local FROM domain WHERE CONCAT("@", domain) IN (%k)';
 EOF
-   if [[ "$?" -ne 0 ]] ; then
-      installation_failed=true
-      error "$(cat $tmp_err_msg)"
+      if [[ "$?" -ne 0 ]] ; then
+         installation_failed=true
+         error "$(cat $tmp_err_msg)"
+      fi
+
    fi
 
 fi