diff --git a/lib/tasks/sync_ntnu_personal_data_tasks.rake b/lib/tasks/sync_ntnu_personal_data_tasks.rake
index c063d37..efa69a8 100644
--- a/lib/tasks/sync_ntnu_personal_data_tasks.rake
+++ b/lib/tasks/sync_ntnu_personal_data_tasks.rake
@@ -3,6 +3,8 @@ module NtnuSyncPlugin
   def self.sync_journal_papers(query_result, user)
     puts "Journal Paper for user: #{user.user_name}"
     journal_papers = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20100421092921000' }
+    return if journal_papers.count == 0
+    JournalPaper.where(member_profile_id: user.member_profile_id).destroy
     journal_papers.each do |journal_paper|
       j_data = JSON.parse(journal_paper['JDATA'])
       jp = JournalPaper.new
@@ -47,6 +49,8 @@ module NtnuSyncPlugin
   def self.sync_conference_papers(query_result, user)
     puts "Conference Paper for user: #{user.user_name}"
     conference_papers = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20100504082700357' }
+    return if conference_papers.count == 0
+    WritingConference.where(member_profile_id: user.member_profile_id).destroy
     conference_papers.each do |conference_paper|
       j_data = JSON.parse(conference_paper['JDATA'])
       wc = WritingConference.new
@@ -106,6 +110,8 @@ module NtnuSyncPlugin
   def self.sync_projects(query_result, user)
     puts "Projects for user: #{user.user_name}"
     projects = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20101113165022345' }
+    return if projects.count == 0
+    Project.where(member_profile_id: user.member_profile_id).destroy
     projects.each do |project|
       j_data = JSON.parse(project['JDATA'])
       pj = Project.new
@@ -161,9 +167,7 @@ module NtnuSyncPlugin
     puts "Academic treatise books for user: #{user.user_name}"
     book_type = BookType.where('title.en' => 'academic treatise books')
     books = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20101113154035616' }
-
     return if books.empty?
-
     books.each do |book|
       j_data = JSON.parse(book['JDATA'])
       bk = Book.new
@@ -215,9 +219,7 @@ module NtnuSyncPlugin
     puts "Academic book chapters for user: #{user.user_name}"
     book_type = BookType.where('title.en' => 'academic book chapters')
     books = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20101113154120441' }
-
     return if books.empty?
-
     books.each do |book|
       j_data = JSON.parse(book['JDATA'])
       bk = Book.new
@@ -273,9 +275,7 @@ module NtnuSyncPlugin
     puts "Officially published university textbooks for user: #{user.user_name}"
     book_type = BookType.where('title.en' => 'officially published university textbooks')
     books = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20101117102418434' }
-
     return if books.empty?
-
     books.each do |book|
       j_data = JSON.parse(book['JDATA'])
       bk = Book.new
@@ -327,9 +327,7 @@ module NtnuSyncPlugin
     puts "Other authored works for user: #{user.user_name}"
     book_type = BookType.where('title.en' => 'other authored works')
     books = query_result.select { |data| data['ER_ACCOUNT'] == user.user_name && data['EI_SN'] == '20101117111154107' }
-
     return if books.empty?
-
     books.each do |book|
       j_data = JSON.parse(book['JDATA'])
       bk = Book.new
@@ -438,13 +436,6 @@ namespace :sync_ntnu_personal_plugins do
     query_result.each do |data|
       available_accounts.add data["ER_ACCOUNT"]
     end
-
-    # Remove Old JournalPaper, xxx, ...
-    JournalPaper.destroy_all
-    WritingConference.destroy_all
-    Project.destroy_all
-    Book.destroy_all
-
     # Create book types
     NtnuSyncPlugin.define_book_types
 
@@ -455,6 +446,17 @@ namespace :sync_ntnu_personal_plugins do
       NtnuSyncPlugin.sync_journal_papers(query_result, user)
       NtnuSyncPlugin.sync_conference_papers(query_result, user)
       NtnuSyncPlugin.sync_projects(query_result, user)
+      books_for_user = query_result.select do |data|
+        tmp = (data['ER_ACCOUNT'] == user.user_name)
+        tmp1 = (data['EI_SN'] == '20101113154035616')
+        tmp2 = (data['EI_SN'] == '20101113154120441')
+        tmp3 = (data['EI_SN'] == '20101117102418434')
+        tmp4 = (data['EI_SN'] == '20101117111154107')
+        tmp && (tmp1 || tmp2 || tmp3 || tmp4)
+      end
+      if books_for_user.count != 0
+        Book.where(member_profile_id: user.member_profile_id,:pages=>nil).destroy
+      end
       NtnuSyncPlugin.sync_academic_treatise_books(query_result, user)
       NtnuSyncPlugin.sync_academic_book_chapters(query_result, user)
       NtnuSyncPlugin.sync_officially_published_university_textbooks(query_result, user)