diff --git a/acme.sh b/acme.sh
index 701da6eb..e1ee3867 100755
--- a/acme.sh
+++ b/acme.sh
@@ -2257,6 +2257,9 @@ _setopt() {
   if [ ! -f "$__conf" ]; then
     touch "$__conf"
   fi
+  if [ -n "$(tail -c 1 <"$__conf")" ]; then
+    echo >>"$__conf"
+  fi
 
   if grep -n "^$__opt$__sep" "$__conf" >/dev/null; then
     _debug3 OK