diff --git a/game/views.py b/game/views.py
index 0c0dad3..a24c1c6 100644
--- a/game/views.py
+++ b/game/views.py
@@ -4,13 +4,13 @@ import google.oauth2.credentials
 import google_auth_oauthlib
 import googleapiclient.discovery
 from django.conf import settings
+from django.contrib import messages
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.contrib.auth.models import User
 from django.contrib.messages.views import SuccessMessageMixin
 from django.db import IntegrityError
 from django.db.models import Count, Q
-from django.http import JsonResponse
-from django.shortcuts import get_object_or_404, redirect
+from django.shortcuts import redirect
 from django.views import View
 from django.views.generic.detail import DetailView, SingleObjectMixin
 from django.views.generic.edit import CreateView, DeleteView, UpdateView
@@ -38,9 +38,8 @@ class GroupMixin:
     fields = ["name"]
 
 
-class GroupCreateView(LoginRequiredMixin, GroupMixin, CreateView):
+class GroupIntegrityMixin:
     def form_valid(self, form):
-        form.instance.owner = self.request.user
         try:
             return super().form_valid(form)
         except IntegrityError:
@@ -48,7 +47,13 @@ class GroupCreateView(LoginRequiredMixin, GroupMixin, CreateView):
             return super().form_invalid(form)
 
 
-class GroupUpdateView(OwnerFilterMixin, GroupMixin, UpdateView):
+class GroupCreateView(LoginRequiredMixin, GroupMixin, GroupIntegrityMixin, CreateView):
+    def form_valid(self, form):
+        form.instance.owner = self.request.user
+        return super().form_valid(form)
+
+
+class GroupUpdateView(OwnerFilterMixin, GroupMixin, GroupIntegrityMixin, UpdateView):
     pass
 
 
@@ -84,14 +89,26 @@ class GroupAddMusicView(MemberFilterMixin, SingleObjectMixin, View):
         group = self.get_object()
         yt_id = request.POST.get("yt_id")
         if not yt_id:
-            return JsonResponse({"error": "You must provide a YouTube ID."}, status=400)
+            messages.add_message(request, messages.ERROR, "Aucun identifiant donné")
+            return redirect(group)
         yt_id = utils.parse_musik(yt_id)
 
         title = utils.get_yt_title(yt_id)
         if not title:
-            return JsonResponse({"error": "Invalid YouTube ID."}, status=400)
-        group.musicvideo_set.create(yt_id=yt_id, title=title, owner=request.user)
-        group.save()
+            messages.add_message(
+                request, messages.ERROR, f"Vidéo Youtube invalide : {yt_id}"
+            )
+            return redirect(group)
+        try:
+            group.musicvideo_set.create(yt_id=yt_id, title=title, owner=request.user)
+        except IntegrityError:
+            messages.add_message(
+                request, messages.ERROR, f"Vidéo Youtube déjà ajoutée : {yt_id}"
+            )
+
+        messages.add_message(
+            request, messages.SUCCESS, f"Vidéo Youtube ajoutée : {yt_id}"
+        )
         return redirect(group)
 
 
@@ -102,6 +119,15 @@ class GroupAddMemberView(OwnerFilterMixin, SingleObjectMixin, View):
         group = self.get_object()
         username = request.POST.get("username")
         user = User.objects.get(username=username)
+        if user == group.owner:
+            messages.add_message(
+                request, messages.WARNING, f"{user} est le propriétaire du groupe."
+            )
+            return redirect(group)
+        if user in group.members.all():
+            messages.add_message(
+                request, messages.WARNING, f"{user} est déjà membre du groupe."
+            )
 
         group.members.add(user)
         return redirect(group)
@@ -117,17 +143,25 @@ class GroupRemoveMusicView(OwnerFilterMixin, SingleObjectMixin, View):
         return redirect(group)
 
 
-class GroupRemoveMemberView(View):
-    def get(self, request, pk, user_pk):
-        relation = get_object_or_404(
-            models.Group.members.through,
-            group_id=pk,
-            user_id=user_pk,
-            group__owner=request.user,
-        )
+class GroupRemoveMemberView(OwnerFilterMixin, SingleObjectMixin, View):
+    model = models.Group
+
+    def get(self, request, pk, user_pk):
+        group = self.get_object()
+        user = User.objects.get(pk=user_pk)
+
+        relation = models.Group.members.through.objects.filter(
+            group=group, user=user
+        ).first()
+        if not relation:
+            messages.add_message(
+                request,
+                messages.ERROR,
+                f"L'utilisateur {user} n'est pas membre du groupe.",
+            )
+        else:
+            relation.delete()
 
-        group = relation.group
-        relation.delete()
         return redirect(group)
 
 
@@ -142,6 +176,11 @@ class GroupRemoveGameView(SingleObjectMixin, SuccessMessageMixin, View):
         game = self.get_object()
         group = game.group
         game.delete()
+        messages.add_message(
+            request,
+            messages.SUCCESS,
+            f"Le jeu du {game.date.strftime('%x')} a été supprimé avec succès.",
+        )
         return redirect(group)
 
 
@@ -255,9 +294,11 @@ class YoutubeLoginView(LoginRequiredMixin, View):
 
 class YoutubeCallbackView(LoginRequiredMixin, View):
     def get(self, request):
-        if request.GET.get("error"):
+        if err := request.GET.get("error"):
+            messages.add_message(
+                request, messages.ERROR, f"Échec de la connexion à Youtube : {err}"
+            )
             return redirect("/")
-        print(request.GET)
 
         state = self.request.session.get("state")
         flow = google_auth_oauthlib.flow.Flow.from_client_secrets_file(
@@ -283,6 +324,8 @@ class YoutubeCallbackView(LoginRequiredMixin, View):
                 }
             },
         )
+
+        messages.add_message(request, messages.SUCCESS, "Connexion à Youtube réussie.")
         return redirect("/")
 
 
@@ -292,4 +335,5 @@ class GroupClearBlacklistView(OwnerFilterMixin, SingleObjectMixin, View):
     def get(self, request, pk):
         group = self.get_object()
         group.musicvideo_set.filter(blacklisted=True).update(blacklisted=False)
+        messages.add_message(request, messages.SUCCESS, "La blacklist a été vidée.")
         return redirect(group)