diff --git a/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFavoriteFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFavoriteFeed.cs
index bdd59d24..053ad487 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFavoriteFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFavoriteFeed.cs
@@ -28,7 +28,8 @@ namespace CampusAppWP8.Feed.Departments
         public DepartmentFavoriteFeed(bool autoLoad = true)
             : base(ModelType.File, Constants.FileDepartment_Favorite_Name, string.Empty)
         {
-            this.isFileUpToDate += new IsFileUpToDate(this.CheckIsFileUpToDate);
+            this.isFileUpToDateOnLoad += new IsFileUpToDate(this.CheckIsFileUpToDateOnLoad);
+            this.isFileUpToDateOnSave += new IsFileUpToDate(this.CheckIsFileUpToDateOnSave);
 
             if (autoLoad == true)
             {
@@ -68,7 +69,7 @@ namespace CampusAppWP8.Feed.Departments
         /// <param name="model">model object</param>
         /// <param name="info">file info object</param>
         /// <returns>true, if file is up-to-date, otherwise false</returns>
-        private bool CheckIsFileUpToDate(DepartmentModel model, FileInfo info)
+        private bool CheckIsFileUpToDateOnLoad(DepartmentModel model, FileInfo info)
         {
             bool retValue = false;
 
@@ -76,11 +77,22 @@ namespace CampusAppWP8.Feed.Departments
             {
                 retValue = true;
             }
-            else
-            {
-                retValue = (model.HasChanged() == false) ? true : false;
-            }
+            
+            return retValue;
+        }
 
+        /// <summary>
+        /// Method implement CheckIsFileUpToDate()-Method <see cref="Pages"/>.
+        /// </summary>
+        /// <param name="model">model object</param>
+        /// <param name="info">file info object</param>
+        /// <returns>true, if file is up-to-date, otherwise false</returns>
+        private bool CheckIsFileUpToDateOnSave(DepartmentModel model, FileInfo info)
+        {
+            bool retValue = false;
+
+            retValue = (model.HasChanged() == false) ? true : false;
+            
             return retValue;
         }
 
diff --git a/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFeed.cs
index e967ec95..93e71301 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/Departments/DepartmentFeed.cs
@@ -27,8 +27,9 @@ namespace CampusAppWP8.Feed.Departments
         public DepartmentFeed(bool autoLoad = true)
             : base(ModelType.FileAndFeed, Constants.FileDepartment_Name, Constants.UrlDepartment_Addr)
         {
-            this.isFileUpToDate += new IsFileUpToDate(this.CheckIsFileUpToDate);
-            this.isModelUpToDate += new IsModelUpToDate(this.CheckIsModelUpToDate);
+            this.isFileUpToDateOnLoad += new IsFileUpToDate(this.CheckIsFileUpToDateOnLoad);
+            this.isFileUpToDateOnSave += new IsFileUpToDate(this.CheckIsFileUpToDateOnSave);
+            this.isModelUpToDateOnLoad += new IsModelUpToDate(this.CheckIsModelUpToDate);
 
             if (autoLoad == true)
             {
@@ -70,7 +71,7 @@ namespace CampusAppWP8.Feed.Departments
         /// <param name="model">model object</param>
         /// <param name="info">file info object</param>
         /// <returns>true, if file is up-to-date, otherwise false</returns>
-        private bool CheckIsFileUpToDate(DepartmentModel model, FileInfo info)
+        private bool CheckIsFileUpToDateOnLoad(DepartmentModel model, FileInfo info)
         {
             bool retValue = true;
 
@@ -82,19 +83,30 @@ namespace CampusAppWP8.Feed.Departments
                     retValue = Utilities.DayDifference(Utilities.DifferenceType.Less, info.LastWriteTime, 7.0);
                 }
             }
-            else 
-            {
-                // at saving
-                if ((info.Exists == false)
-                || (info.Length == 0))
-                {
-                    retValue = false;
-                }
-            }
             
             return retValue;
         }
 
+        /// <summary>
+        /// Method implement CheckIsFileUpToDate()-Method <see cref="Pages"/>.
+        /// </summary>
+        /// <param name="model">model object</param>
+        /// <param name="info">file info object</param>
+        /// <returns>true, if file is up-to-date, otherwise false</returns>
+        private bool CheckIsFileUpToDateOnSave(DepartmentModel model, FileInfo info)
+        {
+            bool retValue = true;
+
+            // at saving
+            if ((info.Exists == false)
+            || (info.Length == 0))
+            {
+                retValue = false;
+            }
+        
+            return retValue;
+        }
+
         // Protedted
         #endregion
 
diff --git a/CampusAppWP8/CampusAppWP8/Feed/Events/EventFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/Events/EventFeed.cs
index 099c8571..3151e488 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/Events/EventFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/Events/EventFeed.cs
@@ -25,8 +25,9 @@ namespace CampusAppWP8.Feed.Events
         public EventFeed(bool autoLoad = true)
             : base(ModelType.FileAndFeed, Constants.FileEvents_Name, Constants.UrlEvents_Addr)
         {
-            this.isFileUpToDate += new IsFileUpToDate(this.CheckIsFileUpToDate);
-            this.isModelUpToDate += new IsModelUpToDate(this.CheckIsModelUpToDate);
+            this.isFileUpToDateOnLoad += new IsFileUpToDate(this.CheckIsFileUpToDateOnLoad);
+            this.isFileUpToDateOnSave += new IsFileUpToDate(this.CheckIsFileUpToDateOnSave);
+            this.isModelUpToDateOnLoad += new IsModelUpToDate(this.CheckIsModelUpToDate);
 
             if (autoLoad == true)
             {
@@ -61,7 +62,7 @@ namespace CampusAppWP8.Feed.Events
         /// <param name="model">model object</param>
         /// <param name="info">file info object</param>
         /// <returns>true, if file is up-to-date, otherwise false</returns>
-        private bool CheckIsFileUpToDate(RSSViewModel model, FileInfo info)
+        private bool CheckIsFileUpToDateOnLoad(RSSViewModel model, FileInfo info)
         {
             bool retValue = true;
 
@@ -73,16 +74,26 @@ namespace CampusAppWP8.Feed.Events
                     retValue = Utilities.DayDifference(Utilities.DifferenceType.Less, info.LastWriteTime, 1.0);
                 }
             }
-            else 
-            {
-                // at saving
-                if ((info.Exists == false)
-                || (info.Length == 0))
-                {
-                    retValue = false;
-                }
-            }
+            
+            return retValue;
+        }
 
+        /// <summary>
+        /// Method implement CheckIsFileUpToDate()-Method <see cref="Pages"/>
+        /// </summary>
+        /// <param name="model">model object</param>
+        /// <param name="info">file info object</param>
+        /// <returns>true, if file is up-to-date, otherwise false</returns>
+        private bool CheckIsFileUpToDateOnSave(RSSViewModel model, FileInfo info)
+        {
+            bool retValue = true;
+
+            if ((info.Exists == false)
+            || (info.Length == 0))
+            {
+                retValue = false;
+            }
+        
             return retValue;
         }
     }
diff --git a/CampusAppWP8/CampusAppWP8/Feed/News/NewsFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/News/NewsFeed.cs
index d6cd0411..b194b720 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/News/NewsFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/News/NewsFeed.cs
@@ -25,8 +25,9 @@ namespace CampusAppWP8.Feed.News
         public NewsFeed(bool autoLoad = true)
             : base(ModelType.FileAndFeed, Constants.FileNews_Name, Constants.UrlNews_Addr)
         {
-            this.isFileUpToDate += new IsFileUpToDate(this.CheckIsFileUpToDate);
-            this.isModelUpToDate += new IsModelUpToDate(this.CheckIsModelUpToDate);
+            this.isFileUpToDateOnLoad += new IsFileUpToDate(this.CheckIsFileUpToDateOnLoad);
+            this.isFileUpToDateOnSave += new IsFileUpToDate(this.CheckIsFileUpToDateOnSave);
+            this.isModelUpToDateOnLoad += new IsModelUpToDate(this.CheckIsModelUpToDate);
 
             if (autoLoad == true)
             {
@@ -61,28 +62,37 @@ namespace CampusAppWP8.Feed.News
         /// <param name="model">model object</param>
         /// <param name="info">info object of the file</param>
         /// <returns>true, if file is up-to-date, otherwise false</returns>
-        private bool CheckIsFileUpToDate(RSSViewModel model, FileInfo info)
+        private bool CheckIsFileUpToDateOnLoad(RSSViewModel model, FileInfo info)
         {
             bool retValue = true;
 
             if (model == null) 
             {
-                // at loading
                 if (info.Exists == true)
                 {
                     retValue = Utilities.DayDifference(Utilities.DifferenceType.Less, info.LastWriteTime, 1.0);
                 }
             }
-            else 
-            {
-                // at saving
-                if ((info.Exists == false)
-                || (info.Length == 0))
-                {
-                    retValue = false;
-                }
-            }
+            
+            return retValue;
+        }
+        
+        /// <summary>
+        /// Method implement CheckIsFileUpToDate()-Method <see cref="Pages"/>
+        /// </summary>
+        /// <param name="model">model object</param>
+        /// <param name="info">info object of the file</param>
+        /// <returns>true, if file is up-to-date, otherwise false</returns>
+        private bool CheckIsFileUpToDateOnSave(RSSViewModel model, FileInfo info)
+        {
+            bool retValue = true;
 
+            if ((info.Exists == false)
+            || (info.Length == 0))
+            {
+                retValue = false;
+            }
+        
             return retValue;
         }
     }
diff --git a/CampusAppWP8/CampusAppWP8/Feed/Openinghours/OpeninghoursFeed.cs b/CampusAppWP8/CampusAppWP8/Feed/Openinghours/OpeninghoursFeed.cs
index d1b0fb71..ae754db0 100644
--- a/CampusAppWP8/CampusAppWP8/Feed/Openinghours/OpeninghoursFeed.cs
+++ b/CampusAppWP8/CampusAppWP8/Feed/Openinghours/OpeninghoursFeed.cs
@@ -12,7 +12,8 @@ namespace CampusAppWP8.Feed.Openinghours
     using CampusAppWP8.Model;
     using CampusAppWP8.Model.Openinghours;
     using CampusAppWP8.Resources;
-
+    using CampusAppWP8.Utility;
+    
     /// <summary>
     /// This Class is for MesaFeeds
     /// </summary>
@@ -26,8 +27,9 @@ namespace CampusAppWP8.Feed.Openinghours
         public OpeninghoursFeed()
             : base(ModelType.FileAndFeed, Constants.FileOpeningHours_OpeningHours,  Constants.UrlOpeningHours_OpeningHours)
         {
-            this.isFileUpToDate += new IsFileUpToDate(this.CheckIsFileUpToDate);
-            this.isModelUpToDate += new IsModelUpToDate(this.CheckIsModelUpToDate);
+            this.isFileUpToDateOnLoad += new IsFileUpToDate(this.CheckIsFileUpToDateOnLoad);
+            this.isFileUpToDateOnSave += new IsFileUpToDate(this.CheckIsFileUpToDateOnSave);
+            this.isModelUpToDateOnLoad += new IsModelUpToDate(this.CheckIsModelUpToDate);
         }
 
         #endregion
@@ -43,35 +45,58 @@ namespace CampusAppWP8.Feed.Openinghours
         /// <returns>true, if model is up-to-date, otherwise false</returns>
         private bool CheckIsModelUpToDate(OpeninghoursModel model)
         {
+            bool retValue = true;
+
             if (model == null)
             {
-                return false;
+                retValue = false;
+            }
+            else
+            {
+                retValue = Utilities.DayDifference(Utilities.DifferenceType.Less, model.CreateTime, 7.0);
             }
 
-            DateTime lastModified = model.CreateTime;
-            return this.CheckIsUpToDate(lastModified);
+            return retValue;
         }
 
         /// <summary>
         /// Method check if the FeedFile is up-to-date
         /// </summary>
         /// <param name="model">reference of the FeedModel</param>
-        /// <param name="fileInfo">info about the file</param>
+        /// <param name="info">info about the file</param>
         /// <returns>true, if file is up-to-date, otherwise false</returns>
-        private bool CheckIsFileUpToDate(OpeninghoursModel model, FileInfo fileInfo)
+        private bool CheckIsFileUpToDateOnLoad(OpeninghoursModel model, FileInfo info)
         {
-            DateTime lastModified = fileInfo.LastWriteTime;
-            return this.CheckIsUpToDate(lastModified);
+            bool retValue = true;
+
+            if (model == null)
+            {
+                if (info.Exists == true)
+                {
+                    retValue = Utilities.DayDifference(Utilities.DifferenceType.Less, info.LastWriteTime, 7.0);
+                }
+            }
+
+            return retValue;
         }
 
         /// <summary>
-        /// Check if the model or file is up-to-date.
+        /// Method check if the FeedFile is up-to-date
         /// </summary>
-        /// <param name="lastModified">Date of the last modification</param>
-        /// <returns>true, if is up-to-date, otherwise false</returns>
-        private bool CheckIsUpToDate(DateTime lastModified)
+        /// <param name="model">reference of the FeedModel</param>
+        /// <param name="info">info about the file</param>
+        /// <returns>true, if file is up-to-date, otherwise false</returns>
+        private bool CheckIsFileUpToDateOnSave(OpeninghoursModel model, FileInfo info)
         {
-            return true;
+            bool retValue = true;
+
+            if ((info.Exists == false)
+            || (info.Length == 0))
+            {
+                retValue = false;
+            }
+
+            return retValue;
         }
 
         #endregion
diff --git a/CampusAppWP8/CampusAppWP8/Model/MainModel.cs b/CampusAppWP8/CampusAppWP8/Model/MainModel.cs
index c37f74cb..ca175cbc 100644
--- a/CampusAppWP8/CampusAppWP8/Model/MainModel.cs
+++ b/CampusAppWP8/CampusAppWP8/Model/MainModel.cs
@@ -143,14 +143,25 @@ namespace CampusAppWP8
         public event OnSaved onSaved = null;
 
         /// <summary>
-        /// Callback pointer, for checking if file is up to date.
+        /// Callback pointer, for checking if file is up to date at loading.
         /// </summary>
-        public event IsFileUpToDate isFileUpToDate = null;
+        public event IsFileUpToDate isFileUpToDateOnLoad = null;
 
         /// <summary>
-        /// Callback pointer, for checking if model is up to date.
+        /// Callback pointer, for checking if file is up to date at saving.
         /// </summary>
-        public event IsModelUpToDate isModelUpToDate = null;
+        public event IsFileUpToDate isFileUpToDateOnSave = null;
+
+        /// <summary>
+        /// Callback pointer, for checking if model is up to date at loading.
+        /// </summary>
+        public event IsModelUpToDate isModelUpToDateOnLoad = null;
+
+        /// <summary>
+        /// Callback pointer, for checking if model is up to date at saving.
+        /// (currently unused)
+        /// </summary>
+        public event IsModelUpToDate isModelUpToDateOnSave = null;
 
         /// <summary>
         /// Specifies the I/O type of the model.
@@ -231,8 +242,8 @@ namespace CampusAppWP8
                 this.onLoading();
             }
 
-            if (((this.isModelUpToDate == null)
-            || (this.isModelUpToDate(this.model) == false))
+            if (((this.isModelUpToDateOnLoad == null)
+            || (this.isModelUpToDateOnLoad(this.model) == false))
             && ((this.file != null) || this.api != null))
             {
                 if (this.file != null)
@@ -243,8 +254,8 @@ namespace CampusAppWP8
                         loadFromFile = false;
                     }
 
-                    if (((this.isFileUpToDate != null) && (this.isFileUpToDate(this.model, this.file.GetFileInfo()) == false))
-                    || (this.isFileUpToDate == null))
+                    if (((this.isFileUpToDateOnLoad != null) && (this.isFileUpToDateOnLoad(this.model, this.file.GetFileInfo()) == false))
+                    || (this.isFileUpToDateOnLoad == null))
                     {
                         loadFromFile = false;
                     }
@@ -289,7 +300,7 @@ namespace CampusAppWP8
         public void SaveData()
         {
             if ((this.file != null)
-            && ((this.isFileUpToDate == null) || (this.isFileUpToDate(this.model, this.file.GetFileInfo()) == false)))
+            && ((this.isFileUpToDateOnSave == null) || (this.isFileUpToDateOnSave(this.model, this.file.GetFileInfo()) == false)))
             {
                 if (this.onSaving != null)
                 {