diff --git a/app/assets/javascripts/app/controllers/_application_controller_form.coffee b/app/assets/javascripts/app/controllers/_application_controller_form.coffee
index e33e18f45..c5b64db52 100644
--- a/app/assets/javascripts/app/controllers/_application_controller_form.coffee
+++ b/app/assets/javascripts/app/controllers/_application_controller_form.coffee
@@ -12,6 +12,10 @@ class App.ControllerForm extends App.Controller
     # set empty class attributes if needed
     if !@form
       @form = @formGen()
+
+    # add alert placeholder
+    @form.prepend('<div class="alert alert--danger js-alert hide" role="alert"></div>')
+
     if !@model
       @model = {}
     if !@attributes
@@ -27,9 +31,18 @@ class App.ControllerForm extends App.Controller
       @form.find('textarea').trigger('change')
       @form.find('select').trigger('change')
 
+    # remove alert on input
+    @form.on('input', @hideAlert)
+
     @finishForm = true
     @form
 
+  showAlert: (message) =>
+    @form.find('.alert').removeClass('hide').html( App.i18n.translateContent( message ) )
+
+  hideAlert: =>
+    @form.find('.alert').addClass('hide').html()
+
   html: =>
     @form.html()
 
diff --git a/app/assets/javascripts/app/controllers/getting_started.coffee b/app/assets/javascripts/app/controllers/getting_started.coffee
index 3b05f7af4..42ee9acb3 100644
--- a/app/assets/javascripts/app/controllers/getting_started.coffee
+++ b/app/assets/javascripts/app/controllers/getting_started.coffee
@@ -228,11 +228,11 @@ class Admin extends App.ControllerContent
         )
         @Config.set('system_init_done', true)
 
-      fail: (data) =>
+      fail: (settings, details) =>
         @formEnable(e)
         App.Event.trigger 'notify', {
           type:    'error'
-          msg:     App.i18n.translateContent( 'Can\'t create user!' )
+          msg:     App.i18n.translateContent( details.error_human || 'Can\'t create user!' )
           timeout: 2500
         }
     )
@@ -984,11 +984,11 @@ class Agent extends App.ControllerContent
         # rerender page
         @render()
 
-      fail: (data) =>
+      fail: (settings, details) =>
         @formEnable(e)
         App.Event.trigger 'notify', {
           type:    'error'
-          msg:     App.i18n.translateContent( 'Can\'t create user!' )
+          msg:     App.i18n.translateContent( details.error_human || 'Can\'t create user!' )
           timeout: 2500
         }
     )
diff --git a/app/assets/javascripts/app/controllers/signup.coffee b/app/assets/javascripts/app/controllers/signup.coffee
index 24105b24d..4400949f0 100644
--- a/app/assets/javascripts/app/controllers/signup.coffee
+++ b/app/assets/javascripts/app/controllers/signup.coffee
@@ -24,7 +24,7 @@ class Index extends App.ControllerContent
 
     @html App.view('signup')()
 
-    new App.ControllerForm(
+    @form = new App.ControllerForm(
       el:        @el.find('form')
       model:     App.User
       screen:    'signup'
@@ -34,7 +34,7 @@ class Index extends App.ControllerContent
   cancel: ->
     @navigate '#login'
 
-  submit: (e) ->
+  submit: (e) =>
     e.preventDefault()
     @formDisable(e)
     @params = @formParam(e.target)
@@ -67,6 +67,9 @@ class Index extends App.ControllerContent
           success: @success
           error: @error
         )
+      fail: (settings, details) =>
+        @formEnable(e)
+        @form.showAlert(details.error_human || details.error || 'Unable to update object!')
     )
 
   success: (data, status, xhr) =>
diff --git a/app/assets/javascripts/app/lib/app_post/ajax.coffee b/app/assets/javascripts/app/lib/app_post/ajax.coffee
index 9f2cf72c8..8bfb5e5db 100644
--- a/app/assets/javascripts/app/lib/app_post/ajax.coffee
+++ b/app/assets/javascripts/app/lib/app_post/ajax.coffee
@@ -73,6 +73,7 @@ class _ajaxSingleton
       # do not show any error message with code 401/404 (handled by controllers)
       return if status is 401
       return if status is 404
+      return if status is 422
 
       # do not show any error message with code 502
       return if status is 502
diff --git a/app/assets/javascripts/app/lib/spine/ajax.coffee b/app/assets/javascripts/app/lib/spine/ajax.coffee
index ed2639878..1370780db 100644
--- a/app/assets/javascripts/app/lib/spine/ajax.coffee
+++ b/app/assets/javascripts/app/lib/spine/ajax.coffee
@@ -166,7 +166,14 @@ class Collection extends Base
   failResponse: (options) =>
     (xhr, statusText, error, settings) =>
       @model.trigger('ajaxError', null, xhr, statusText, error, settings)
-      options.fail?.call(@model, settings)
+      # add errors to calllback
+      @record.trigger('ajaxError', @record, xhr, statusText, error, settings)
+      #options.fail?.call(@model, settings)
+      detailsRaw = xhr.responseText
+      if !_.isEmpty(detailsRaw)
+        details = JSON.parse(detailsRaw)
+      options.fail?.call(@record, settings, details)
+      # /add errors to calllback
 
 class Singleton extends Base
   constructor: (@record) ->
@@ -230,8 +237,15 @@ class Singleton extends Base
       switch settings.type
         when 'POST' then @createFailed()
         when 'DELETE' then @destroyFailed()
+      # add errors to calllback
       @record.trigger('ajaxError', @record, xhr, statusText, error, settings)
-      options.fail?.call(@record, settings)
+      #options.fail?.call(@record, settings)
+      detailsRaw = xhr.responseText
+      if !_.isEmpty(detailsRaw)
+        details = JSON.parse(detailsRaw)
+      options.fail?.call(@record, settings, details)
+      @record.trigger('remove', @record)
+      # /add errors to calllback
 
   createFailed: ->
     @record.remove(clear: true)
diff --git a/app/assets/javascripts/app/models/_application_model.coffee b/app/assets/javascripts/app/models/_application_model.coffee
index 39a284abc..d1d182880 100644
--- a/app/assets/javascripts/app/models/_application_model.coffee
+++ b/app/assets/javascripts/app/models/_application_model.coffee
@@ -307,7 +307,7 @@ class App.Model extends Spine.Model
 
       # subscribe and render data / fetch new data if triggered
       @bind(
-        'refresh change'
+        'refresh change remove'
         (items) =>
           App.Log.debug('Model', "local collection refresh/change #{@className}", items)
           for key, callback of @SUBSCRIPTION_COLLECTION
@@ -376,6 +376,19 @@ class App.Model extends Spine.Model
               item = App[ @className ]._fillUp( item )
               callback(item, 'change')
       )
+      @bind(
+        'remove'
+        (items) =>
+
+          # check if result is array or singel item
+          if !_.isArray(items)
+            items = [items]
+          App.Log.debug('Model', "local remove #{@className}", items)
+          for item in items
+            for key, callback of App[ @className ].SUBSCRIPTION_ITEM[ item.id ]
+              item = App[ @className ]._fillUp( item )
+              callback(item, 'remove')
+      )
 
       @changeTable = {}
       @bind(
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 6f4cc4170..665abdbed 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -313,7 +313,7 @@ class ApplicationController < ActionController::Base
   rescue => e
     logger.error e.message
     logger.error e.backtrace.inspect
-    render json: { error: e.message }, status: :unprocessable_entity
+    render json: model_match_error(e.message), status: :unprocessable_entity
   end
 
   def model_create_render_item (generic_object)
@@ -335,7 +335,7 @@ class ApplicationController < ActionController::Base
   rescue => e
     logger.error e.message
     logger.error e.backtrace.inspect
-    render json: { error: e.message }, status: :unprocessable_entity
+    render json: model_match_error(e.message), status: :unprocessable_entity
   end
 
   def model_update_render_item (generic_object)
@@ -349,7 +349,7 @@ class ApplicationController < ActionController::Base
   rescue => e
     logger.error e.message
     logger.error e.backtrace.inspect
-    render json: { error: e.message }, status: :unprocessable_entity
+    render json: model_match_error(e.message), status: :unprocessable_entity
   end
 
   def model_destory_render_item ()
@@ -369,7 +369,7 @@ class ApplicationController < ActionController::Base
   rescue => e
     logger.error e.message
     logger.error e.backtrace.inspect
-    render json: { error: e.message }, status: :unprocessable_entity
+    render json: model_match_error(e.message), status: :unprocessable_entity
   end
 
   def model_show_render_item (generic_object)
@@ -382,11 +382,20 @@ class ApplicationController < ActionController::Base
   rescue => e
     logger.error e.message
     logger.error e.backtrace.inspect
-    render json: { error: e.message }, status: :unprocessable_entity
+    render json: model_match_error(e.message), status: :unprocessable_entity
   end
 
   def model_index_render_result (generic_objects)
     render json: generic_objects, status: :ok
   end
 
+  def model_match_error (error)
+    data = {
+      error: error
+    }
+    if error =~ /(already exists|duplicate key)/i
+      data[:error_human] = 'Object already exists!'
+    end
+    data
+  end
 end
diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index 0a82973ba..f23a357b7 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -77,7 +77,7 @@ class UsersController < ApplicationController
 
         # check if feature is enabled
         if !Setting.get('user_create_account')
-          render json: { error: 'Feature not enabled!' }, status: :unprocessable_entity
+          render json: { error_human: 'Feature not enabled!' }, status: :unprocessable_entity
           return
         end
 
@@ -117,7 +117,7 @@ class UsersController < ApplicationController
       if user.email
         exists = User.where(email: user.email.downcase).first
         if exists
-          render json: { error: 'User already exists!' }, status: :unprocessable_entity
+          render json: { error_human: 'User already exists!' }, status: :unprocessable_entity
           return
         end
       end
@@ -180,7 +180,7 @@ class UsersController < ApplicationController
       user_new = User.find(user.id)
       render json: user_new, status: :created
     rescue => e
-      render json: { error: e.message }, status: :unprocessable_entity
+      render json: model_match_error(e.message), status: :unprocessable_entity
     end
   end