diff --git a/src/main/java/info/istlab/IoTP/ScriptRunner.java b/src/main/java/info/istlab/IoTP/ScriptRunner.java
index ab89b69..4b099c3 100644
--- a/src/main/java/info/istlab/IoTP/ScriptRunner.java
+++ b/src/main/java/info/istlab/IoTP/ScriptRunner.java
@@ -43,7 +43,7 @@
         // System.out.println(scriptfile);
         ArrayList<String> comlist = new ArrayList<String>();
         if (App.isWindows) {
-            SerialWindow.check();
+            SerialWindow.check(false);
             comlist.add("cmd");
             comlist.add("/c");
             comlist.add("start");
@@ -52,6 +52,8 @@
                 comlist.add(srcfile);
             if (App.serialName != null)
                 comlist.add(App.serialName);
+            else
+                comlist.add("null");
         } else {
             comlist.add("bash");
             comlist.add("Upload.sh");
@@ -94,7 +96,7 @@
         con.Systemoutprintln("=== 終了 === (ALT+Wで閉じる)");
         thread = null;
         // runB.setText("Run");
-        SerialWindow.invoke();
+        SerialWindow.invoke(!App.isWindows); // windowsなら、no serial connectionsのとき、メッセージ表示しない
         if (App.isWindows) {
             con.frame.dispose();
         }
diff --git a/src/main/java/info/istlab/IoTP/SerialWindow.java b/src/main/java/info/istlab/IoTP/SerialWindow.java
index a72fb42..88e66a2 100644
--- a/src/main/java/info/istlab/IoTP/SerialWindow.java
+++ b/src/main/java/info/istlab/IoTP/SerialWindow.java
@@ -39,7 +39,7 @@
     /**
      * チェックして、App.serialName にポート名をセットするだけ。
      */
-    public static void check(){
+    public static void check(boolean popup_if_zero){
         SerialPort[] ports = SerialPort.getCommPorts();
         ArrayList<SerialPort> splist_valid = new ArrayList<SerialPort>();
         for (SerialPort sp : ports) {
@@ -52,14 +52,13 @@
             SerialPort sp = splist_valid.get(0);
             App.serialName = sp.getSystemPortName();
         } else if (splist_valid.size()==0){
-            JOptionPane.showMessageDialog(null, "No available serial ports.");
+            if (popup_if_zero) JOptionPane.showMessageDialog(null, "No available serial ports.");
         } else {
             SerialSelector.show(splist_valid.toArray(new SerialPort[]{}));
         }
-
     }
 
-    public static void invoke() {
+    public static void invoke(boolean popup_if_zero) {
         SerialPort[] ports = SerialPort.getCommPorts();
         ArrayList<SerialPort> splist_valid = new ArrayList<SerialPort>();
         for (SerialPort sp : ports) {