Django 2.0 'name' is not a registered namespace

Try to change your app_name='' in learning_logs/urls.py. (Create if there is not any.)

In the first learning_logs app you forgot s in the end (e.g. app_name = 'learning_logs')

There are two ways can hanlded this.

Firstly,you can set an app_name attribute in the included URLconf module, at the same level as the urlpatterns attribute. You have to pass the actual module, or a string reference to the module, to include(), not the list of urlpatterns itself.

https://docs.djangoproject.com/en/2.0/topics/http/urls/#url-namespaces-and-included-urlconfs

urls.py

from django.urls import include, path

urlpatterns = [
    path('polls/', include('polls.urls')),
]

polls/urls.py

from django.urls import path

from . import views

app_name = 'polls'
urlpatterns = [
    path('', views.IndexView.as_view(), name='index'),
    path('<int:pk>/', views.DetailView.as_view(), name='detail'),
    ...
]

have fun!