diff --git a/app/controllers/dmsf_workflows_controller.rb b/app/controllers/dmsf_workflows_controller.rb
index a7b213b1..126fd262 100644
--- a/app/controllers/dmsf_workflows_controller.rb
+++ b/app/controllers/dmsf_workflows_controller.rb
@@ -51,8 +51,7 @@ class DmsfWorkflowsController < ApplicationController
                 begin
                   file.unlock! true
                 rescue DmsfLockError => e
-                  flash[:info] = e.message
-                  #logger.warn e.message
+                  flash[:info] = e.message                  
                 end
               end              
               if revision.workflow == DmsfWorkflow::STATE_APPROVED
@@ -171,28 +170,27 @@ class DmsfWorkflowsController < ApplicationController
   end
   
   def assignment
-    if params[:commit] == l(:button_submit)
+    if (params[:commit] == l(:button_submit)) && 
+        params[:dmsf_workflow_id].present? && (params[:dmsf_workflow_id] != '-1')
       revision = DmsfFileRevision.find_by_id params[:dmsf_file_revision_id]
       if revision
-        revision.set_workflow(params[:dmsf_workflow_id], params[:action])
-        if params[:dmsf_workflow_id].present?
-          revision.assign_workflow(params[:dmsf_workflow_id])
-          if request.post? 
-            if revision.save
-              file = DmsfFile.find_by_id revision.dmsf_file_id
-              if file
-                begin
-                  file.lock!
-                rescue DmsfLockError => e
-                  logger.warn e.message
-                end
-                flash[:notice] = l(:notice_successful_update)                
+        revision.set_workflow(params[:dmsf_workflow_id], params[:action])        
+        revision.assign_workflow(params[:dmsf_workflow_id])
+        if request.post? 
+          if revision.save
+            file = DmsfFile.find_by_id revision.dmsf_file_id
+            if file
+              begin
+                file.lock!
+              rescue DmsfLockError => e
+                logger.warn e.message
               end
-            else
-              flash[:error] = l(:error_workflow_assign)
+              flash[:notice] = l(:notice_successful_update)                
             end
+          else
+            flash[:error] = l(:error_workflow_assign)
           end
-        end
+        end        
       end    
     end
     redirect_to :back        
diff --git a/app/helpers/dmsf_workflows_helper.rb b/app/helpers/dmsf_workflows_helper.rb
index 90ca653a..d930bb76 100644
--- a/app/helpers/dmsf_workflows_helper.rb
+++ b/app/helpers/dmsf_workflows_helper.rb
@@ -55,6 +55,7 @@ module DmsfWorkflowsHelper
   
   def dmsf_workflows_for_select(project, dmsf_workflow_id)
     options = Array.new        
+    options << ['', -1]
     DmsfWorkflow.sorted.where(['project_id = ? OR project_id IS NULL', project.id]).each do |wf|
       if wf.project_id
         options << [wf.name, wf.id]
diff --git a/app/views/dmsf_workflows/_assign.html.erb b/app/views/dmsf_workflows/_assign.html.erb
index e5a6070f..83be9a13 100644
--- a/app/views/dmsf_workflows/_assign.html.erb
+++ b/app/views/dmsf_workflows/_assign.html.erb
@@ -1,6 +1,6 @@
 <%# Redmine plugin for Document Management System "Features"
 #
-# Copyright (C) 2011/15 Karel Pičman <karel.picman@kontron.com>
+# Copyright (C) 2011-15 Karel Pičman <karel.picman@kontron.com>
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU General Public License