diff --git a/amadeus/static/css/base/amadeus.css b/amadeus/static/css/base/amadeus.css
index ff2078c..1487500 100755
--- a/amadeus/static/css/base/amadeus.css
+++ b/amadeus/static/css/base/amadeus.css
@@ -115,7 +115,7 @@
 
 .category-header .dropdown-menu i {
     font-size: 20px !important;
-    float: auto;
+    float: none;
 }
 
 .category-header i{
diff --git a/categories/templates/categories/list.html b/categories/templates/categories/list.html
index 820f960..24868a2 100755
--- a/categories/templates/categories/list.html
+++ b/categories/templates/categories/list.html
@@ -16,7 +16,11 @@
     {% if messages %}
         {% for message in messages %}
             <script type="text/javascript">
-                alertify.success('{{message}}');
+                {% if message.tags == "danger" %}
+                    alertify.error('{{message}}');
+                {% else %}
+                    alertify.success('{{message}}');
+                {% endif %}
             </script>
         {% endfor %}
     {% endif %}
diff --git a/categories/views.py b/categories/views.py
index a9201f9..ad4af6f 100644
--- a/categories/views.py
+++ b/categories/views.py
@@ -1,4 +1,4 @@
-from django.shortcuts import render, get_object_or_404
+from django.shortcuts import render, get_object_or_404, redirect
 from django.views.generic import ListView, CreateView, DeleteView, UpdateView
 from .models import Category
 from django.core.urlresolvers import reverse_lazy
@@ -139,17 +139,20 @@ class DeleteCategory(LogMixin, DeleteView):
 
     login_url = reverse_lazy("users:login")
     redirect_field_name = 'next'
+
     model = Category
     template_name = 'categories/delete.html'
 
     def delete(self, request, *args, **kwargs):
         category = get_object_or_404(Category, slug = self.kwargs.get('slug'))
         subjects = Subject.objects.filter(category = category)
+
+        print(self.request.META.get('HTTP_REFERER'))
         
         if subjects.count() > 0:
-            #objeto = category
-            #messages.success(self.request, _('cannot delete Category "%s" ')%(objeto))
-            return reverse_lazy('categories:index')
+            messages.error(self.request, _('The category cannot be removed, it contains one or more virtual enviroments attach.'))
+
+            return redirect(self.request.META.get('HTTP_REFERER'))
        
         return super(DeleteCategory, self).delete(self, request, *args, **kwargs)
 
@@ -161,8 +164,8 @@ class DeleteCategory(LogMixin, DeleteView):
         super(DeleteCategory, self).createLog(self.request.user, self.log_component, self.log_action, self.log_resource, self.log_context)
 
         messages.success(self.request, _('Category removed successfully!'))
-        return reverse_lazy('categories:index')
 
+        return self.request.META.get('HTTP_REFERER')
 
 class UpdateCategory(LogMixin, UpdateView):
     log_component = 'category'
diff --git a/subjects/templates/subjects/list.html b/subjects/templates/subjects/list.html
index a228682..0d9e2e5 100644
--- a/subjects/templates/subjects/list.html
+++ b/subjects/templates/subjects/list.html
@@ -20,10 +20,15 @@
     {% if messages %}
         {% for message in messages %}
             <script type="text/javascript">
-                alertify.success('{{message}}');
+                {% if message.tags == "danger" %}
+                    alertify.error('{{message}}');
+                {% else %}
+                    alertify.success('{{message}}');
+                {% endif %}
             </script>
         {% endfor %}
-    {% endif %}    
+    {% endif %}
+
     <div id="core-subjects-options-div">
         <ul class="core-subjects-options">
             {% if all %}
diff --git a/users/views.py b/users/views.py
index 15da600..ecf1fd4 100644
--- a/users/views.py
+++ b/users/views.py
@@ -1,4 +1,4 @@
-from django.shortcuts import get_object_or_404,redirect, render
+from django.shortcuts import get_object_or_404, redirect, render
 from django.views import generic
 from django.contrib import messages
 from django.contrib.auth import authenticate, login as login_user
--
libgit2 0.21.2