diff --git a/machines/forms.py b/machines/forms.py
index 241ce303..23c2aa39 100644
--- a/machines/forms.py
+++ b/machines/forms.py
@@ -262,7 +262,6 @@ class ExtensionForm(FormRevMixin, ModelForm):
         self.fields['origin'].label = 'Enregistrement A origin'
         self.fields['origin_v6'].label = 'Enregistrement AAAA origin'
         self.fields['soa'].label = 'En-tête SOA à utiliser'
-        self.fielss['mail_extension'].label = 'Utilisable comme extension mail'
 
 
 class DelExtensionForm(FormRevMixin, Form):
diff --git a/machines/models.py b/machines/models.py
index c8dccadf..7be76e74 100644
--- a/machines/models.py
+++ b/machines/models.py
@@ -546,10 +546,6 @@ class Extension(RevMixin, AclMixin, models.Model):
         'SOA',
         on_delete=models.CASCADE
     )
-    mail_extension = models.BooleanField(
-        default=False,
-        help_text="Determine si l'extension peut être utilisée comme extension mail interne"
-    )
 
     class Meta:
         permissions = (
diff --git a/preferences/migrations/0035_optionaluser_mail_extension.py b/preferences/migrations/0035_optionaluser_mail_extension.py
new file mode 100644
index 00000000..3d1b42b4
--- /dev/null
+++ b/preferences/migrations/0035_optionaluser_mail_extension.py
@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-06-26 19:31
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('preferences', '0034_auto_20180416_1120'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='optionaluser',
+            name='mail_extension',
+            field=models.CharField(default='@example.org', help_text='Extension principale pour les mails internes', max_length=32),
+        ),
+    ]
diff --git a/preferences/models.py b/preferences/models.py
index d39b9f8e..516de515 100644
--- a/preferences/models.py
+++ b/preferences/models.py
@@ -31,6 +31,8 @@ from django.db.models.signals import post_save
 from django.dispatch import receiver
 from django.core.cache import cache
 
+from django.forms import ValidationError
+import cotisations.models
 import machines.models
 from re2o.mixins import AclMixin
 
@@ -83,12 +85,25 @@ class OptionalUser(AclMixin, PreferencesModel):
         blank=True,
         null=True
     )
+    mail_extension = models.CharField(
+        max_length = 32,
+        default = "@example.org",
+        help_text="Extension principale pour les mails internes",
+    )
 
     class Meta:
         permissions = (
             ("view_optionaluser", "Peut voir les options de l'user"),
         )
 
+    def clean(self):
+        """Clean du model:
+        Creation du mode de paiement par solde
+        Vérifie que l'extension mail commence bien par @
+        """
+        if self.mail_extension[0] != "@":
+            raise ValidationError("L'extension mail doit commencer par un @")
+    
 
 @receiver(post_save, sender=OptionalUser)
 def optionaluser_post_save(**kwargs):
diff --git a/preferences/templates/preferences/display_preferences.html b/preferences/templates/preferences/display_preferences.html
index 34417695..c232f13c 100755
--- a/preferences/templates/preferences/display_preferences.html
+++ b/preferences/templates/preferences/display_preferences.html
@@ -56,6 +56,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
                 <th>Creations de clubs par tous</th>
                 <td>{{ useroptions.all_can_create_club|tick }}</td>
         </tr>
+	<tr>
+                <th>Extension mail interne</th>
+                <td>{{ useroptions.mail_extension }}</td>
+	</tr>
 </table>
 
 
diff --git a/users/admin.py b/users/admin.py
index 5f4c197b..92528455 100644
--- a/users/admin.py
+++ b/users/admin.py
@@ -127,7 +127,6 @@ class UserAdmin(VersionAdmin, BaseUserAdmin):
     list_display = (
         'pseudo',
         'surname',
-        'email',
         'school',
         'is_admin',
         'shell'
@@ -141,7 +140,7 @@ class UserAdmin(VersionAdmin, BaseUserAdmin):
             'Personal info',
             {
                 'fields':
-                ('surname', 'email', 'school', 'shell', 'uid_number')
+                ('surname', 'school', 'shell', 'uid_number')
             }
         ),
         ('Permissions', {'fields': ('is_admin', )}),
@@ -156,7 +155,6 @@ class UserAdmin(VersionAdmin, BaseUserAdmin):
                 'fields': (
                     'pseudo',
                     'surname',
-                    'email',
                     'school',
                     'is_admin',
                     'password1',
diff --git a/users/forms.py b/users/forms.py
index ba8e137e..a3459eac 100644
--- a/users/forms.py
+++ b/users/forms.py
@@ -140,7 +140,7 @@ class UserCreationForm(FormRevMixin, forms.ModelForm):
 
     class Meta:
         model = Adherent
-        fields = ('pseudo', 'surname', 'email')
+        fields = ('pseudo', 'surname')
 
     def clean_password2(self):
         """Verifie que password1 et 2 sont identiques"""
@@ -220,7 +220,7 @@ class UserChangeForm(FormRevMixin, forms.ModelForm):
 
     class Meta:
         model = Adherent
-        fields = ('pseudo', 'password', 'surname', 'email')
+        fields = ('pseudo', 'password', 'surname')
 
     def __init__(self, *args, **kwargs):
         prefix = kwargs.pop('prefix', self.Meta.model.__name__)
@@ -313,7 +313,6 @@ class AdherentForm(FormRevMixin, FieldPermissionFormMixin, ModelForm):
             'name',
             'surname',
             'pseudo',
-            'email',
             'school',
             'comment',
             'room',
@@ -365,7 +364,6 @@ class ClubForm(FormRevMixin, FieldPermissionFormMixin, ModelForm):
         fields = [
             'surname',
             'pseudo',
-            'email',
             'school',
             'comment',
             'room',
diff --git a/users/migrations/0073_mail_mailalias.py b/users/migrations/0073_mail_mailalias.py
new file mode 100644
index 00000000..ce676464
--- /dev/null
+++ b/users/migrations/0073_mail_mailalias.py
@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-06-26 19:07
+from __future__ import unicode_literals
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+import re2o.mixins
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('users', '0072_auto_20180426_2021'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Mail',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('external_mail', models.EmailField(help_text='Mail externe', max_length=254)),
+                ('redirection', models.BooleanField(default=False)),
+                ('internal_address', models.BooleanField(default=False)),
+                ('user', models.OneToOneField(help_text="Object mail d'un User", on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+            bases=(re2o.mixins.RevMixin, re2o.mixins.AclMixin, models.Model),
+        ),
+        migrations.CreateModel(
+            name='MailAlias',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('valeur', models.CharField(help_text="username de l'adresse mail", max_length=64, unique=True)),
+                ('mail', models.ForeignKey(help_text='Objects Mail associé', on_delete=django.db.models.deletion.CASCADE, to='users.Mail')),
+            ],
+            bases=(re2o.mixins.RevMixin, re2o.mixins.AclMixin, models.Model),
+        ),
+    ]
diff --git a/users/migrations/0074_transfermail.py b/users/migrations/0074_transfermail.py
new file mode 100644
index 00000000..dbf6adca
--- /dev/null
+++ b/users/migrations/0074_transfermail.py
@@ -0,0 +1,36 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-06-26 18:34
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('users', '0073_mail_mailalias'),
+    ]
+
+    def create_mail(apps, schema_editor):
+        db_alias = schema_editor.connection.alias
+        user = apps.get_model('users','User')
+        mail = apps.get_model('users','Mail')
+        mailalias = apps.get_model('users','MailAlias')
+        users = user.objects.using(db_alias).all()
+        for us in users:
+            ma = mail()
+            ma.user=us
+            ma.external_mail = us.email
+            ma.save()
+            al = mailalias()
+            al.mail = ma
+            al.valeur = us.pseudo
+            al.save()
+
+    def uncreatemail(apps,schema_editor):
+        pass
+
+    operations = [
+        migrations.RunPython(create_mail, uncreatemail)
+    ]
diff --git a/users/models.py b/users/models.py
index f5e2039f..bbdbef58 100644
--- a/users/models.py
+++ b/users/models.py
@@ -79,7 +79,7 @@ from re2o.field_permissions import FieldPermissionModelMixin
 from re2o.mixins import AclMixin, RevMixin
 
 from cotisations.models import Cotisation, Facture, Paiement, Vente
-from machines.models import Domain, Interface, Machine, regen, Extension
+from machines.models import Domain, Interface, Machine, regen
 from preferences.models import GeneralOption, AssoOption, OptionalUser
 from preferences.models import OptionalMachine, MailMessageOption
 
@@ -134,7 +134,6 @@ class UserManager(BaseUserManager):
             self,
             pseudo,
             surname,
-            email,
             password=None,
             su=False
     ):
@@ -148,7 +147,6 @@ class UserManager(BaseUserManager):
             pseudo=pseudo,
             surname=surname,
             name=surname,
-            email=self.normalize_email(email),
         )
 
         user.set_password(password)
@@ -157,19 +155,19 @@ class UserManager(BaseUserManager):
         user.save(using=self._db)
         return user
 
-    def create_user(self, pseudo, surname, email, password=None):
+    def create_user(self, pseudo, surname, password=None):
         """
         Creates and saves a User with the given pseudo, name, surname, email,
         and password.
         """
-        return self._create_user(pseudo, surname, email, password, False)
+        return self._create_user(pseudo, surname, password, False)
 
-    def create_superuser(self, pseudo, surname, email, password):
+    def create_superuser(self, pseudo, surname, password):
         """
         Creates and saves a superuser with the given pseudo, name, surname,
         email, and password.
         """
-        return self._create_user(pseudo, surname, email, password, True)
+        return self._create_user(pseudo, surname, password, True)
 
 
 class User(RevMixin, FieldPermissionModelMixin, AbstractBaseUser,
@@ -188,19 +186,13 @@ class User(RevMixin, FieldPermissionModelMixin, AbstractBaseUser,
     )
 
     surname = models.CharField(max_length=255)
+    email = models.EmailField()
     pseudo = models.CharField(
         max_length=32,
         unique=True,
         help_text="Doit contenir uniquement des lettres, chiffres, ou tirets",
         validators=[linux_user_validator]
     )
-    email = models.EmailField()
-    """
-    email= models.OneToOneField(
-            Mail,
-            on_delete=models.PROTECT
-    )
-    """
     school = models.ForeignKey(
         'School',
         on_delete=models.PROTECT,
@@ -233,7 +225,7 @@ class User(RevMixin, FieldPermissionModelMixin, AbstractBaseUser,
     )
 
     USERNAME_FIELD = 'pseudo'
-    REQUIRED_FIELDS = ['surname', 'email']
+    REQUIRED_FIELDS = ['surname']
 
     objects = UserManager()
 
@@ -686,10 +678,10 @@ class User(RevMixin, FieldPermissionModelMixin, AbstractBaseUser,
         """
         Return the mail address choosen by the user
         """
-        if not self.mail.internal_activated:
-            return(self.mail.external)
+        if not self.mail.internal_address:
+            return self.mail.external_mail
         else:
-            return(self.mail.mailalias_set.first())
+            return self.mail.mailalias_set.get(valeur=pseudo)
 
     def get_next_domain_name(self):
         """Look for an available name for a new interface for
@@ -1619,7 +1611,7 @@ class Mail(RevMixin, AclMixin, models.Model):
     Compte mail d'un utilisateur
     """
     external_mail = models.EmailField(help_text="Mail externe")
-    user = models.ForeignKey(
+    user = models.OneToOneField(
             'User',
             on_delete=models.CASCADE,
             help_text="Object mail d'un User"
@@ -1632,7 +1624,7 @@ class Mail(RevMixin, AclMixin, models.Model):
     )
     
     def __str__(self):
-        return self.mail
+        return self.user.get_mail()
 
 
 class MailAlias(RevMixin, AclMixin, models.Model):
@@ -1647,20 +1639,14 @@ class MailAlias(RevMixin, AclMixin, models.Model):
         help_text="Objects Mail associé"
     )
     valeur = models.CharField(
+        unique=True,
         max_length=64,
         help_text="username de l'adresse mail"
     )
-    extension = models.ForeignKey(
-        'machines.Extension',
-        on_delete=models.CASCADE,
-        help_text="Extension mail interne"
-    )
 
-    class Meta:
-        unique_together = ('valeur', 'extension',)
 
     def __str__(self):
-        return self.valeur + "@" + self.extension
+        return self.valeur + OptionalUser.get_cached_value('mail_extension')
 
     def can_view(self, user_request, *_args, **_kwargs):
         """
@@ -1681,7 +1667,7 @@ class MailAlias(RevMixin, AclMixin, models.Model):
             return True, None
         else:
             if user_request == self.mail.user:
-                if self.id != 0:
+                if self.valeur == self.mail.user.pseudo:
                     return True, None
                 else:
                     return False, "Vous ne pouvez pas supprimer l'alias lié à votre pseudo"
@@ -1697,7 +1683,7 @@ class MailAlias(RevMixin, AclMixin, models.Model):
             return True, None
         else:
             if user_request == self.mail.user:
-                if self.id != 0:
+                if self.valeur == self.mail.user.pseudo:
                     return True, None
                 else:
                     return False, "Vous ne pouvez pas modifier l'alias lié à votre pseudo"
diff --git a/users/views.py b/users/views.py
index b2a83dbe..c8061040 100644
--- a/users/views.py
+++ b/users/views.py
@@ -81,6 +81,8 @@ from .models import (
     Adherent,
     Club,
     ListShell,
+    MailAlias,
+    Mail,
 )
 from .forms import (
     BanForm,