diff --git a/Plugins/Wox.Plugin.Program/AddProgramSource.xaml.cs b/Plugins/Wox.Plugin.Program/AddProgramSource.xaml.cs
index 97456bea1..b959cc518 100644
--- a/Plugins/Wox.Plugin.Program/AddProgramSource.xaml.cs
+++ b/Plugins/Wox.Plugin.Program/AddProgramSource.xaml.cs
@@ -49,14 +49,15 @@ private void ButtonAdd_OnClick(object sender, RoutedEventArgs e)
 
             if(_editing == null)
             {
-                _settings.ProgramSources.Add(new ProgramSource
+                var source = new ProgramSource
                 {
                     Location = Directory.Text,
                     MaxDepth = max,
                     Suffixes = Suffixes.Text.Split(ProgramSource.SuffixSeperator),
                     Type = "FileSystemProgramSource",
                     Enabled = true
-                });
+                };
+                _settings.ProgramSources.Add(source);
             }
             else
             {
diff --git a/Plugins/Wox.Plugin.Program/StringEmptyConverter.cs b/Plugins/Wox.Plugin.Program/LocationConverter.cs
similarity index 53%
rename from Plugins/Wox.Plugin.Program/StringEmptyConverter.cs
rename to Plugins/Wox.Plugin.Program/LocationConverter.cs
index d09806362..bd28bc944 100644
--- a/Plugins/Wox.Plugin.Program/StringEmptyConverter.cs
+++ b/Plugins/Wox.Plugin.Program/LocationConverter.cs
@@ -5,20 +5,26 @@
 
 namespace Wox.Plugin.Program
 {
-    public class StringEmptyConverter : MarkupExtension, IValueConverter
+    public class LocationConverter : MarkupExtension, IValueConverter
     {
         public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
         {
-            return string.IsNullOrEmpty((string)value) ? parameter : value;
+            var text = value as string;
+            if (string.IsNullOrEmpty(text))
+            {
+                return string.Empty;
+            }
+            else
+            {
+                return text;
+            }
         }
 
-        public object ConvertBack(
-              object value, Type targetType, object parameter, CultureInfo culture)
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
         {
             throw new NotSupportedException();
         }
 
-
         public override object ProvideValue(IServiceProvider serviceProvider)
         {
             return this;
diff --git a/Plugins/Wox.Plugin.Program/ProgramSetting.xaml b/Plugins/Wox.Plugin.Program/ProgramSetting.xaml
index af8616cab..5711e2383 100644
--- a/Plugins/Wox.Plugin.Program/ProgramSetting.xaml
+++ b/Plugins/Wox.Plugin.Program/ProgramSetting.xaml
@@ -28,14 +28,14 @@
                     <GridViewColumn Header="{DynamicResource wox_plugin_program_location}"  Width="250">
                         <GridViewColumn.CellTemplate>
                             <DataTemplate>
-                                <TextBlock Text="{Binding Location, ConverterParameter=(null), Converter={program:StringEmptyConverter}}"/>
+                                <TextBlock Text="{Binding Location, ConverterParameter=(null), Converter={program:LocationConverter}}"/>
                             </DataTemplate>
                         </GridViewColumn.CellTemplate>
                     </GridViewColumn>
                     <GridViewColumn Header="{DynamicResource wox_plugin_program_suffixes_header}"  Width="220">
                         <GridViewColumn.CellTemplate>
                             <DataTemplate>
-                                <TextBlock Text="{Binding Suffixes, ConverterParameter=(null), Converter={program:StringEmptyConverter}}"/>
+                                <TextBlock Text="{Binding Suffixes, ConverterParameter=(null), Converter={program:SuffixesConvert}}"/>
                             </DataTemplate>
                         </GridViewColumn.CellTemplate>
                     </GridViewColumn>
diff --git a/Plugins/Wox.Plugin.Program/SuffixesConverter.cs b/Plugins/Wox.Plugin.Program/SuffixesConverter.cs
new file mode 100644
index 000000000..11d76e5b3
--- /dev/null
+++ b/Plugins/Wox.Plugin.Program/SuffixesConverter.cs
@@ -0,0 +1,33 @@
+using System;
+using System.Globalization;
+using System.Windows.Data;
+using System.Windows.Markup;
+
+namespace Wox.Plugin.Program
+{
+    public class SuffixesConvert : MarkupExtension, IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            var text = value as string[];
+            if (text != null)
+            {
+                return string.Join("", text);
+            }
+            else
+            {
+                return string.Empty;
+            }
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            throw new NotSupportedException();
+        }
+
+        public override object ProvideValue(IServiceProvider serviceProvider)
+        {
+            return this;
+        }
+    }
+}
diff --git a/Plugins/Wox.Plugin.Program/Wox.Plugin.Program.csproj b/Plugins/Wox.Plugin.Program/Wox.Plugin.Program.csproj
index 4d2807a9c..4b38f99d9 100644
--- a/Plugins/Wox.Plugin.Program/Wox.Plugin.Program.csproj
+++ b/Plugins/Wox.Plugin.Program/Wox.Plugin.Program.csproj
@@ -62,6 +62,7 @@
     </Compile>
     <Compile Include="FileChangeWatcher.cs" />
     <Compile Include="IProgramSource.cs" />
+    <Compile Include="SuffixesConverter.cs" />
     <Compile Include="Program.cs" />
     <Compile Include="ProgramIndexCache.cs" />
     <Compile Include="Programs.cs" />
@@ -77,7 +78,7 @@
     <Compile Include="ProgramSuffixes.xaml.cs">
       <DependentUpon>ProgramSuffixes.xaml</DependentUpon>
     </Compile>
-    <Compile Include="StringEmptyConverter.cs" />
+    <Compile Include="LocationConverter.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>
   <ItemGroup>