diff --git a/app/controllers/dmsf_files_copy_controller.rb b/app/controllers/dmsf_files_copy_controller.rb
index a185c6b2..fff62bd0 100644
--- a/app/controllers/dmsf_files_copy_controller.rb
+++ b/app/controllers/dmsf_files_copy_controller.rb
@@ -117,7 +117,10 @@ class DmsfFilesCopyController < ApplicationController
 private
 
   def log_activity(file, action)
-    Rails.logger.info "#{Time.now.strftime('%Y-%m-%d %H:%M:%S')} #{User.current.login}@#{request.remote_ip}/#{request.env['HTTP_X_FORWARDED_FOR']}: #{action} dmsf://#{file.project.identifier}/#{file.id}/#{file.last_revision.id}"
+    if file && file.last_revision
+      Rails.logger.info
+        "#{Time.now.strftime('%Y-%m-%d %H:%M:%S')} #{User.current.login}@#{request.remote_ip}/#{request.env['HTTP_X_FORWARDED_FOR']}: #{action} dmsf://#{file.project.identifier}/#{file.id}/#{file.last_revision.id}"
+    end
   end
 
   def find_file
diff --git a/app/models/dmsf_link.rb b/app/models/dmsf_link.rb
index 33e3a1db..cba58487 100644
--- a/app/models/dmsf_link.rb
+++ b/app/models/dmsf_link.rb
@@ -77,7 +77,7 @@ class DmsfLink < ActiveRecord::Base
   def target_file
     unless @target_file
       if self.target_file_id
-        DmsfFile.find_by_id self.target_file_id
+        @target_file = DmsfFile.find_by_id self.target_file_id
       end
     end
     @target_file
@@ -85,7 +85,7 @@ class DmsfLink < ActiveRecord::Base
 
   def target_project
     unless @target_project
-      Project.find_by_id self.target_project_id
+      @target_project = Project.find_by_id self.target_project_id
     end
     @target_project
   end