diff --git a/app/controllers/ticket_articles_controller.rb b/app/controllers/ticket_articles_controller.rb
index c804eff09..c799dd508 100644
--- a/app/controllers/ticket_articles_controller.rb
+++ b/app/controllers/ticket_articles_controller.rb
@@ -125,7 +125,7 @@ class TicketArticlesController < ApplicationController
     # find file
     file = Store.find(params[:id])
     send_data(
-      file.store_file.data,
+      file.content,
       :filename    => file.filename,
       :type        => file.preferences['Content-Type'] || file.preferences['Mime-Type'],
       :disposition => 'inline'
@@ -148,7 +148,7 @@ class TicketArticlesController < ApplicationController
     if list
       file = Store.find(list.first)
       send_data(
-        file.store_file.data,
+        file.content,
         :filename    => file.filename,
         :type        => 'message/rfc822',
         :disposition => 'inline'
diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index 6d4f4c207..b57ba7125 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -598,7 +598,7 @@ curl http://localhost/api/v1/users/image/8d6cca1c6bdc226cf2ba131e264ca2c7 -v -u
       if list && list[0]
         file = Store.find( list[0] )
         send_data(
-          file.store_file.data,
+          file.content,
           :filename    => file.filename,
           :type        => file.preferences['Content-Type'] || file.preferences['Mime-Type'],
           :disposition => 'inline'
diff --git a/app/models/application_model.rb b/app/models/application_model.rb
index 1976cce15..81f035f8d 100644
--- a/app/models/application_model.rb
+++ b/app/models/application_model.rb
@@ -810,7 +810,7 @@ store attachments for this object
       article_store.push Store.add(
         :object        => self.class.to_s,
         :o_id          => self.id,
-        :data          => attachment.store_file.data,
+        :data          => attachment.content,
         :filename      => attachment.filename,
         :preferences   => attachment.preferences,
         :created_by_id => self.created_by_id,
diff --git a/app/models/channel/email_build.rb b/app/models/channel/email_build.rb
index d3c77754c..b9870d6f7 100644
--- a/app/models/channel/email_build.rb
+++ b/app/models/channel/email_build.rb
@@ -41,7 +41,7 @@ class Channel::EmailBuild
         mail.attachments[attachment.filename] = {
           :content_type => attachment.preferences['Content-Type'],
           :mime_type    => attachment.preferences['Mime-Type'],
-          :content      => attachment.store_file.data
+          :content      => attachment.content
         }
       end
     end
diff --git a/app/models/package.rb b/app/models/package.rb
index 11347c178..e0c4d2dc4 100644
--- a/app/models/package.rb
+++ b/app/models/package.rb
@@ -352,11 +352,10 @@ class Package < ApplicationModel
     if !list || !list.first
       raise "No such file in storage list #{name} #{version}"
     end
-    store_file = list.first.store_file
-    if !store_file
+    if !list.first.content
       raise "No such file in storage #{name} #{version}"
     end
-    store_file.data
+    list.first.content
   end
 
   def self._read_file(file, fullpath = false)
@@ -374,7 +373,7 @@ class Package < ApplicationModel
     rescue => e
       raise 'ERROR: ' + e.inspect
     end
-    return contents
+    contents
   end
 
   def self._write_file(file, permission, data)
@@ -411,7 +410,7 @@ class Package < ApplicationModel
     rescue => e
       raise 'ERROR: ' + e.inspect
     end
-    return true
+    true
   end
 
   def self._delete_file(file, permission, data)
diff --git a/app/models/store.rb b/app/models/store.rb
index d887d1bad..a99ce1535 100644
--- a/app/models/store.rb
+++ b/app/models/store.rb
@@ -8,6 +8,26 @@ class Store < ApplicationModel
   belongs_to  :store_file,            :class_name => 'Store::File'
   validates   :filename,              :presence => true
 
+=begin
+
+add an attachment to storage
+
+  result = Store.add(
+    :object       => 'Ticket::Article',
+    :o_id         => 4711,
+    :data         => binary_string,
+    :preferences  => {
+      :content_type => 'image/png',
+      :content_id   => 234,
+    }
+  )
+
+returns
+
+  result = true
+
+=end
+
   def self.add(data)
     data = data.stringify_keys
 
@@ -31,7 +51,7 @@ class Store < ApplicationModel
     if file == nil
       file = Store::File.create(
         :data => data['data'],
-        :md5  => md5
+        :md5  => md5,
       )
     end
 
@@ -44,9 +64,34 @@ class Store < ApplicationModel
     # store meta data
     store = Store.create(data)
 
-    return store
+    true
   end
 
+=begin
+
+get attachment of object
+
+  list = Store.list(
+    :object       => 'Ticket::Article',
+    :o_id         => 4711,
+  )
+
+returns
+
+  result = [store1, store2]
+
+  store1 = {
+    :size         => 94123,
+    :filename     => 'image.png',
+    :preferences  => {
+      :content_type => 'image/png',
+      :content_id   => 234,
+    }
+  }
+  store1.content # binary_string
+
+=end
+
   def self.list(data)
     # search
     store_object_id = Store::Object.lookup( :name => data[:object] )
@@ -55,6 +100,21 @@ class Store < ApplicationModel
     return stores
   end
 
+=begin
+
+remove an attachment to storage
+
+  result = Store.remove(
+    :object       => 'Ticket::Article',
+    :o_id         => 4711,
+  )
+
+returns
+
+  result = true
+
+=end
+
   def self.remove(data)
     # search
     store_object_id = Store::Object.lookup( :name => data[:object] )
@@ -62,22 +122,141 @@ class Store < ApplicationModel
     where( :o_id => data[:o_id] ).
     order('created_at ASC, id ASC')
     stores.each do |store|
+
+      # check backend for references
+      files = Store.where( :store_file_id => store.store_file_id )
+      if files.count == 1 && files.first.id == store.id
+        Store::File.find( store.store_file_id ).destroy
+      end
+
       store.destroy
     end
     return true
   end
 
-  class Object < ApplicationModel
-    validates :name, :presence => true
+  # get attachment
+  def content
+    file = Store::File.where( :id => self.store_file_id ).first
+    return if !file
+    if file.file_system
+      return file.read_from_fs
+    end
+    file.data
+  end
+end
+
+class Store::Object < ApplicationModel
+  validates :name, :presence => true
+end
+
+class Store::File < ApplicationModel
+  before_validation :add_md5
+  before_create     :check_location
+
+  # generate file location
+  def get_locaton
+
+    # generate directory
+    base = Rails.root.to_s + "/storage/fs/"
+    path = self.md5.scan(/./).join('/')
+    location = "#{ base }/#{path}"
+
+    # create directory if not exists
+    if !File.exist?( location )
+      FileUtils.mkdir_p( location )
+    end
+    location += "/file"
   end
 
-  class File < ApplicationModel
-    before_validation :add_md5
+  # read file from fs
+  def read_from_fs
+    puts "read from fs #{self.get_locaton}"
+    return if !File.exist?( self.get_locaton )
+    data = File.open( self.get_locaton, 'rb' )
+    content = data.read
 
-    private
-    def add_md5
-      self.md5 = Digest::MD5.hexdigest( self.data )
+    # check md5
+    md5 = Digest::MD5.hexdigest( content )
+    if md5 != self.md5
+      raise "ERROR: Corrupt file in fs #{self.get_locaton}, md5 should be #{self.md5} but is #{md5}"
+    end
+    content
+  end
+
+  # write file to fs
+  def write_to_fs
+
+    # install file
+    permission = '600'
+    if !File.exist?( self.get_locaton )
+      puts "NOTICE: storge write '#{self.get_locaton}' (#{permission})"
+      file = File.new( self.get_locaton, 'wb' )
+      file.write( self.data )
+      file.close
+    end
+    File.chmod( permission.to_i(8), self.get_locaton )
+
+    # check md5
+    md5 = Digest::MD5.hexdigest( self.read_from_fs )
+    if md5 != self.md5
+      raise "ERROR: Corrupt file in fs #{self.get_locaton}, md5 should be #{self.md5} but is #{md5}"
+    end
+
+    true
+  end
+
+  # write file to db
+  def write_to_db
+
+    # read and check md5
+    content = self.read_from_fs
+
+    # store in database
+    self.data = content
+    self.save
+
+    # check md5 against db content
+    md5 = Digest::MD5.hexdigest( self.data )
+    if md5 != self.md5
+      raise "ERROR: Corrupt file in db #{self.get_locaton}, md5 should be #{self.md5} but is #{md5}"
+    end
+
+    true
+  end
+
+  def self.move_to_fs
+    Store::File.where( :file_system => false ).each {|item|
+      item.write_to_fs
+      item.update_attribute( :file_system, true )
+      item.update_attribute( :data, nil )
+    }
+  end
+
+  def self.move_to_db
+    Store::File.where( :file_system => true ).each {|item|
+      item.write_to_db
+      item.update_attribute( :file_system, false )
+      if File.exist?( item.get_locaton )
+        puts "NOTICE: storge remove '#{item.get_locaton}'"
+        File.delete( item.get_locaton )
+      end
+    }
+  end
+
+  private
+
+  def check_location
+
+    # write initial to fs if needed
+    if self.file_system && self.data
+      self.write_to_fs
+      self.data = nil
     end
   end
 
-end
+  def add_md5
+    if self.data && !self.md5
+      self.md5 = Digest::MD5.hexdigest( self.data )
+    end
+  end
+end
\ No newline at end of file
diff --git a/app/models/ticket/search_index.rb b/app/models/ticket/search_index.rb
index 19de07e08..f97044414 100644
--- a/app/models/ticket/search_index.rb
+++ b/app/models/ticket/search_index.rb
@@ -67,7 +67,7 @@ returns
         end
         data = {
           "_name"   => attachment.filename,
-          "content" => Base64.encode64( attachment.store_file.data )
+          "content" => Base64.encode64( attachment.content )
         }
         article_attributes['attachments'].push data
       }
diff --git a/db/migrate/20120101000030_create_storage.rb b/db/migrate/20120101000030_create_storage.rb
index e59a9a8bc..e12166a74 100644
--- a/db/migrate/20120101000030_create_storage.rb
+++ b/db/migrate/20120101000030_create_storage.rb
@@ -11,7 +11,7 @@ class CreateStorage < ActiveRecord::Migration
       t.timestamps
     end
     add_index :stores, [:store_object_id, :o_id]
-    
+
     create_table :store_objects do |t|
       t.column :name,         :string, :limit => 250,   :null => false
       t.column :note,         :string, :limit => 250,   :null => true
@@ -20,8 +20,8 @@ class CreateStorage < ActiveRecord::Migration
     add_index :store_objects, [:name],   :unique => true
 
     create_table :store_files do |t|
-      t.column :data,     :binary,        :limit => 100.megabytes
-      t.column :md5,      :string,        :limit => 60,  :null => false
+      t.column :data,     :binary,        :limit => 200.megabytes,  :null => true
+      t.column :md5,      :string,        :limit => 60,             :null => false
       t.timestamps
     end
     add_index :store_files, [:md5],   :unique => true
diff --git a/db/migrate/20130925000001_create_activity_stream.rb b/db/migrate/20130925000001_create_activity_stream.rb
index 027a3cbdb..34bb3a99a 100644
--- a/db/migrate/20130925000001_create_activity_stream.rb
+++ b/db/migrate/20130925000001_create_activity_stream.rb
@@ -1,6 +1,5 @@
 class CreateActivityStream < ActiveRecord::Migration
   def up
-    
     create_table :activity_streams do |t|
       t.references :activity_stream_type,                   :null => false
       t.references :activity_stream_object,                 :null => false
diff --git a/db/migrate/20140427000001_update_storage.rb b/db/migrate/20140427000001_update_storage.rb
new file mode 100644
index 000000000..ccf58b030
--- /dev/null
+++ b/db/migrate/20140427000001_update_storage.rb
@@ -0,0 +1,9 @@
+class UpdateStorage < ActiveRecord::Migration
+  def up
+    change_column :store_files, :data,              :binary, :limit => 200.megabytes, :null => true
+    add_column    :store_files, :file_system,       :boolean,                         :null => false, :default => false
+  end
+
+  def down
+  end
+end
diff --git a/test/unit/store_test.rb b/test/unit/store_test.rb
index 51cd1af2d..ed497ca9e 100644
--- a/test/unit/store_test.rb
+++ b/test/unit/store_test.rb
@@ -1,32 +1,33 @@
 # encoding: utf-8
 require 'test_helper'
- 
+
 class StoreTest < ActiveSupport::TestCase
   test 'store attachment' do
     files = [
       {
         :data        => 'hello world',
         :filename    => 'test.txt',
+        :o_id        => 1,
       },
       {
         :data        => 'hello world äöüß',
         :filename    => 'testäöüß.txt',
+        :o_id        => 2,
       },
       {
         :data        => IO.read('test/fixtures/test1.pdf'),
         :filename    => 'test.pdf',
-      },      
+        :o_id        => 3,
+      },
     ]
-    
 
     files.each { |file|
-      
       md5 = Digest::MD5.hexdigest( file[:data] )
 
       # add attachments
       store = Store.add(
         :object        => 'Test',
-        :o_id          => 1,
+        :o_id          => file[:o_id],
         :data          => file[:data],
         :filename      => file[:filename],
         :preferences   => {},
@@ -37,24 +38,76 @@ class StoreTest < ActiveSupport::TestCase
       # get list of attachments
       attachments = Store.list(
         :object => 'Test',
-        :o_id   => 1
+        :o_id   => file[:o_id],
       )
       assert attachments
-  
+
       # md5 check
-      md5_new = Digest::MD5.hexdigest( attachments[0].store_file.data )
-      assert_equal( md5, md5_new )
+      md5_new = Digest::MD5.hexdigest( attachments[0].content )
+      assert_equal( md5, md5_new,  "check file #{ file[:filename] }")
 
       # filename check
       assert_equal( file[:filename], attachments[0].filename )
 
-      # delete attachments
+    }
+
+    Store::File.move_to_fs
+
+    files.each { |file|
+      md5 = Digest::MD5.hexdigest( file[:data] )
+
+      # get list of attachments
+      attachments = Store.list(
+        :object => 'Test',
+        :o_id   => file[:o_id],
+      )
+      assert attachments
+
+      # md5 check
+      md5_new = Digest::MD5.hexdigest( attachments[0].content )
+      assert_equal( md5, md5_new,  "check file #{ file[:filename] }")
+
+      # filename check
+      assert_equal( file[:filename], attachments[0].filename )
+    }
+
+    Store::File.move_to_db
+
+    files.each { |file|
+      md5 = Digest::MD5.hexdigest( file[:data] )
+
+      # get list of attachments
+      attachments = Store.list(
+        :object => 'Test',
+        :o_id   => file[:o_id],
+      )
+      assert attachments
+
+      # md5 check
+      md5_new = Digest::MD5.hexdigest( attachments[0].content )
+      assert_equal( md5, md5_new,  "check file #{ file[:filename] }")
+
+      # filename check
+      assert_equal( file[:filename], attachments[0].filename )
+    }
+
+    # delete attachments
+    files.each { |file|
       success = Store.remove(
         :object => 'Test',
-        :o_id   => 1
+        :o_id   => file[:o_id],
       )
       assert success
-    }    
+    }
+
+    # check attachments again
+    files.each { |file|
+      attachments = Store.list(
+        :object => 'Test',
+        :o_id   => file[:o_id],
+      )
+      assert !attachments[0]
+    }
   end
 end