diff --git a/CampusAppWP8/CampusAppWP8/Feed/Mensa/MensaFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/Mensa/MensaFeed.cs
index da1b043b..2386beb0 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/Mensa/MensaFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/Mensa/MensaFeed.cs
@@ -44,7 +44,11 @@ namespace CampusAppWP8.Api.Mensa
         /// <returns>true, if model is up-to-date, otherwise false</returns>
         private bool CheckIsModelUpToDate(MenuWeekModel model)
         {
-            DateTime lastModified = this.Model.CreateTime;
+            if (model == null)
+            {
+                return false;
+            }
+            DateTime lastModified = model.CreateTime;
             return this.CheckIsUpToDate(lastModified);
         }
 
diff --git a/CampusAppWP8/CampusAppWP8/Resources/Constants.Designer.cs b/CampusAppWP8/CampusAppWP8/Resources/Constants.Designer.cs
index a223d9b3..2d193a50 100644
--- a/CampusAppWP8/CampusAppWP8/Resources/Constants.Designer.cs
+++ b/CampusAppWP8/CampusAppWP8/Resources/Constants.Designer.cs
@@ -115,7 +115,7 @@ namespace CampusAppWP8.Resources {
         }
         
         /// <summary>
-        ///   Sucht eine lokalisierte Zeichenfolge, die  ähnelt.
+        ///   Sucht eine lokalisierte Zeichenfolge, die IsolatedStorage_DepartmentFavoriteModel ähnelt.
         /// </summary>
         public static string IsolatedStorage_DepartmentFavoriteModel {
             get {
@@ -150,15 +150,6 @@ namespace CampusAppWP8.Resources {
             }
         }
         
-        /// <summary>
-        ///   Sucht eine lokalisierte Zeichenfolge, die  ähnelt.
-        /// </summary>
-        public static string LinkApp_CommonLinks {
-            get {
-                return ResourceManager.GetString("LinkApp_CommonLinks", resourceCulture);
-            }
-        }
-        
         /// <summary>
         ///   Sucht eine lokalisierte Zeichenfolge, die Studiengang ähnelt.
         /// </summary>
diff --git a/CampusAppWP8/CampusAppWP8/Resources/Constants.resx b/CampusAppWP8/CampusAppWP8/Resources/Constants.resx
index e9085ad5..d0190478 100644
--- a/CampusAppWP8/CampusAppWP8/Resources/Constants.resx
+++ b/CampusAppWP8/CampusAppWP8/Resources/Constants.resx
@@ -190,7 +190,7 @@
     <value>/Pages/Openinghours/OpeninghoursPage.xaml</value>
   </data>
   <data name="IsolatedStorage_DepartmentFavoriteModel" xml:space="preserve">
-    <value />
+    <value>IsolatedStorage_DepartmentFavoriteModel</value>
   </data>
   <data name="FileDepartment_Favorite_Name" xml:space="preserve">
     <value>DepartmentFavoriteFeed.xml</value>
@@ -249,9 +249,6 @@
   <data name="UrlStudentCouncil_StudentCouncils" xml:space="preserve">
     <value>http://www.tu-cottbus.de/campusapp-data/getdata.php?db=studentcouncils&amp;app=2&amp;appversion=1</value>
   </data>
-  <data name="LinkApp_CommonLinks" xml:space="preserve">
-    <value />
-  </data>
   <data name="FileMensa_Shedule" xml:space="preserve">
     <value>MensaFeed.xml</value>
   </data>
diff --git a/CampusAppWP8/CampusAppWP8/Utility/Lui/Button/NavigateButton.cs b/CampusAppWP8/CampusAppWP8/Utility/Lui/Button/NavigateButton.cs
index 147921b0..2f0a02a5 100644
--- a/CampusAppWP8/CampusAppWP8/Utility/Lui/Button/NavigateButton.cs
+++ b/CampusAppWP8/CampusAppWP8/Utility/Lui/Button/NavigateButton.cs
@@ -24,12 +24,12 @@ namespace CampusAppWP8.Utility.Lui.Button
         public static readonly DependencyProperty NavigateProperty = DependencyProperty.Register("Url", typeof(object), typeof(NavigateButton), new PropertyMetadata(false));
 
         /// <summary>
-        ///  Register the QuerryValueProperty
+        ///  Register the QueryValueProperty
         /// </summary>
         public static readonly DependencyProperty QueryValueProperty = DependencyProperty.Register("QuerryStringValue", typeof(object), typeof(NavigateButton), new PropertyMetadata(false));
 
         /// <summary>
-        ///  Register the QuerryNameProperty
+        ///  Register the QueryNameProperty
         /// </summary>
         public static readonly DependencyProperty QueryNameProperty = DependencyProperty.Register("QuerryStringName", typeof(object), typeof(NavigateButton), new PropertyMetadata(false));
 
@@ -59,7 +59,7 @@ namespace CampusAppWP8.Utility.Lui.Button
         }
 
         /// <summary>
-        /// Gets or sets the QuerryStringName
+        /// Gets or sets the QueryStringName
         /// </summary>
         public object QuerryStringName
         {
@@ -68,7 +68,7 @@ namespace CampusAppWP8.Utility.Lui.Button
         }
 
         /// <summary>
-        /// Gets or sets the QuerryStringValue
+        /// Gets or sets the QueryStringValue
         /// </summary>
         public object QuerryStringValue
         {
diff --git a/CampusAppWP8/CampusAppWP8/model/MainModel.cs b/CampusAppWP8/CampusAppWP8/model/MainModel.cs
index e3a5617f..d2346440 100644
--- a/CampusAppWP8/CampusAppWP8/model/MainModel.cs
+++ b/CampusAppWP8/CampusAppWP8/model/MainModel.cs
@@ -67,7 +67,7 @@ namespace CampusAppWP8
             this.fileName = fileName;
 
             if ((this.IsFile() == true)
-            && (fileName.Equals(string.Empty) == false))
+                && (fileName.Equals(string.Empty) == false))
             {
                 this.InitFile(CampusAppWP8.Utility.File.IOTypeRead.ReadSync, CampusAppWP8.Utility.File.IOTypeWrite.WriteAsync);
             }
diff --git a/CampusAppWP8/CampusAppWP8/pages/StartPage.xaml b/CampusAppWP8/CampusAppWP8/pages/StartPage.xaml
index a2857099..f78cc114 100644
--- a/CampusAppWP8/CampusAppWP8/pages/StartPage.xaml
+++ b/CampusAppWP8/CampusAppWP8/pages/StartPage.xaml
@@ -88,7 +88,7 @@
             </lui:NavigateButton>
 
             <!-- Row 2 -->
-            <lui:NavigateButton Name="DepartmentAppButton" Grid.Row="2" Grid.Column="0" Style="{StaticResource StartPageButton}" IsEnabled="False">
+            <lui:NavigateButton Name="DepartmentAppButton" Grid.Row="2" Grid.Column="0" Style="{StaticResource StartPageButton}"  Url="{Binding Path=Constants.PathDepartment_DepartmentIndexPage, Source={StaticResource Const}}">
                 <StackPanel  Style="{StaticResource StartPageStackPanelStyle}">
                     <Image Source="{Binding Path=ThemelizedIcon.Departments, Source={StaticResource ThemelizedIcons}}" Style="{StaticResource StartPageButtonImg}"/>
                     <TextBlock Text="{Binding Path=LocalizedResources.DepartmentApp_Title, Source={StaticResource LocalizedStrings}}"  Style="{StaticResource StartPageButtonText}"/>