diff --git a/install.sh b/install.sh
index 002a3cb..96cb7e0 100755
--- a/install.sh
+++ b/install.sh
@@ -393,6 +393,9 @@ parse_flags ()
                 break
                 ;;
             *)
+                if [[ $1 != '-h' ]] && [[ $1 != '--help' ]]; then
+                    echo "Invalid option $1"
+                fi
                 echo "
 Usage: "${0}" [options]
 
diff --git a/test/run_tests.sh b/test/run_tests.sh
index 504eb79..4ab8f72 100755
--- a/test/run_tests.sh
+++ b/test/run_tests.sh
@@ -122,6 +122,9 @@ parse_flags ()
                 break
                 ;;
             *)
+                if [[ $1 != '-h' ]] && [[ $1 != '--help' ]]; then
+                    echo "Invalid option $1"
+                fi
                 echo "
 Usage: "${0}" [options]