diff --git a/Flow.Launcher.Core/Resource/Theme.cs b/Flow.Launcher.Core/Resource/Theme.cs
index fe64e0c3e..e7a19d6a4 100644
--- a/Flow.Launcher.Core/Resource/Theme.cs
+++ b/Flow.Launcher.Core/Resource/Theme.cs
@@ -28,6 +28,8 @@ namespace Flow.Launcher.Core.Resource
         private string DirectoryPath => Path.Combine(Constant.ProgramDirectory, Folder);
         private string UserDirectoryPath => Path.Combine(DataLocation.DataDirectory(), Folder);
 
+        public bool BlurEnabled { get; set; }
+
         public Theme()
         {
             _themeDirectories.Add(DirectoryPath);
@@ -88,7 +90,9 @@ namespace Flow.Launcher.Core.Resource
                     _oldTheme = Path.GetFileNameWithoutExtension(_oldResource.Source.AbsolutePath);
                 }
 
-                if (Settings.UseDropShadowEffect)
+                BlurEnabled = IsBlurTheme();
+
+                if (Settings.UseDropShadowEffect && !BlurEnabled)
                     AddDropShadowEffectToCurrentTheme();
             }
             catch (DirectoryNotFoundException e)
@@ -252,7 +256,7 @@ namespace Flow.Launcher.Core.Resource
             UpdateResourceDictionary(dict);
         }
 
-        public void RemoveDropShadowEffectToCurrentTheme()
+        public void RemoveDropShadowEffectFromCurrentTheme()
         {
             var dict = CurrentThemeResourceDictionary();
             var windowBorderStyle = dict["WindowBorderStyle"] as Style;
@@ -320,30 +324,29 @@ namespace Flow.Launcher.Core.Resource
         /// </summary>
         public void SetBlurForWindow()
         {
+            if (BlurEnabled)
+            {
+                SetWindowAccent(Application.Current.MainWindow, AccentState.ACCENT_ENABLE_BLURBEHIND);
+            }
+            else
+            {
+                SetWindowAccent(Application.Current.MainWindow, AccentState.ACCENT_DISABLED);
+            }
+        }
 
-            // Exception of FindResource can't be cathed if global exception handle is set
+        private bool IsBlurTheme()
+        {
             if (Environment.OSVersion.Version >= new Version(6, 2))
             {
                 var resource = Application.Current.TryFindResource("ThemeBlurEnabled");
-                bool blur;
-                if (resource is bool)
-                {
-                    blur = (bool)resource;
-                }
-                else
-                {
-                    blur = false;
-                }
 
-                if (blur)
-                {
-                    SetWindowAccent(Application.Current.MainWindow, AccentState.ACCENT_ENABLE_BLURBEHIND);
-                }
-                else
-                {
-                    SetWindowAccent(Application.Current.MainWindow, AccentState.ACCENT_DISABLED);
-                }
+                if (resource is bool)
+                    return (bool)resource;
+
+                return false;
             }
+
+            return false;
         }
 
         private void SetWindowAccent(Window w, AccentState state)
diff --git a/Flow.Launcher/MainWindow.xaml.cs b/Flow.Launcher/MainWindow.xaml.cs
index 4355cda15..177953912 100644
--- a/Flow.Launcher/MainWindow.xaml.cs
+++ b/Flow.Launcher/MainWindow.xaml.cs
@@ -61,7 +61,8 @@ namespace Flow.Launcher
             // show notify icon when flowlauncher is hidden
             InitializeNotifyIcon();
 
-            // todo is there a way to set blur only once?
+            // currently blur can only be called when loading main window. 
+            // is there a way to set blur only once?
             ThemeManager.Instance.SetBlurForWindow();
             WindowsInteropHelper.DisableControlBox(this);
             InitProgressbarAnimation();
diff --git a/Flow.Launcher/SettingWindow.xaml b/Flow.Launcher/SettingWindow.xaml
index 0d966f1d6..1a8a12100 100644
--- a/Flow.Launcher/SettingWindow.xaml
+++ b/Flow.Launcher/SettingWindow.xaml
@@ -242,7 +242,7 @@
                                 <RowDefinition Height="30"/>
                             </Grid.RowDefinitions>
                             <TextBlock Grid.Row="0" Text="{DynamicResource queryWindowShadowEffect}" Margin="0 30 0 0" FontSize="14" />
-                            <ui:ToggleSwitch Grid.Row="0" IsOn="{Binding DropShadowEffect}" Margin="210 23 0 0" Width="80"/>
+                            <ui:ToggleSwitch Grid.Row="0" IsOn="{Binding DropShadowEffect, Mode=TwoWay}" Margin="210 23 0 0" Width="80"/>
                             <TextBlock  Grid.Row="1" Text="{DynamicResource shadowEffectCPUUsage}"
                                         Width="280"
                                         FontSize="10" HorizontalAlignment="Left"/>
diff --git a/Flow.Launcher/ViewModel/SettingWindowViewModel.cs b/Flow.Launcher/ViewModel/SettingWindowViewModel.cs
index b974efd03..b476599b5 100644
--- a/Flow.Launcher/ViewModel/SettingWindowViewModel.cs
+++ b/Flow.Launcher/ViewModel/SettingWindowViewModel.cs
@@ -271,6 +271,10 @@ namespace Flow.Launcher.ViewModel
             {
                 Settings.Theme = value;
                 ThemeManager.Instance.ChangeTheme(value);
+                
+                if (ThemeManager.Instance.BlurEnabled && Settings.UseDropShadowEffect)
+                    DropShadowEffect = false;
+
             }
         }
 
@@ -282,13 +286,19 @@ namespace Flow.Launcher.ViewModel
             get { return Settings.UseDropShadowEffect; }
             set
             {
+                if (ThemeManager.Instance.BlurEnabled && value)
+                {
+                    MessageBox.Show(InternationalizationManager.Instance.GetTranslation("pleaseSelectAnItem"));
+                    return;
+                }
+
                 if (value)
                 {
                     ThemeManager.Instance.AddDropShadowEffectToCurrentTheme();
                 }
                 else
                 {
-                    ThemeManager.Instance.RemoveDropShadowEffectToCurrentTheme();
+                    ThemeManager.Instance.RemoveDropShadowEffectFromCurrentTheme();
                 }
 
                 Settings.UseDropShadowEffect = value;