diff --git a/EZPPClient Installer/MainWindow.xaml.cs b/EZPPClient Installer/MainWindow.xaml.cs
index 8908b6b..92f536b 100644
--- a/EZPPClient Installer/MainWindow.xaml.cs	
+++ b/EZPPClient Installer/MainWindow.xaml.cs	
@@ -36,6 +36,9 @@ namespace EZPPClient_Installer
 
     public MainWindow()
     {
+      var alreadyRunning = System.Diagnostics.Process.GetProcessesByName(System.IO.Path.GetFileNameWithoutExtension(System.Reflection.Assembly.GetEntryAssembly().Location)).Count() > 1;
+      if (alreadyRunning)
+        this.Close();
       Instance = this;
       InitializeComponent();
       Init();