[Django]-Django E.408, E.409 and E.410 errors on runserver

Rename variables in settings.py, or add this:

MIDDLEWARE = MIDDLEWARE_CLASSES

to settings.py
because new Django triggers errors above based on checks like this:

if not _contains_subclass(
   'django.contrib.auth.middleware.AuthenticationMiddleware', 
   settings.MIDDLEWARE
):
   errors.append(checks.Error( ...

Change setting.py as pic shows
Change setting.py

# MIDDLEWARE_CLASSES = [
MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    # 'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

Also See: From CSDN

1) Go to settings.py of your project

2) Cut these three lines from MIDDLEWARE_CLASSES :

    'django.contrib.sessions.middleware.SessionMiddleware', 
    'django.contrib.messages.middleware.MessageMiddleware', 
    'django.contrib.auth.middleware.AuthenticationMiddleware',

3) Now paste the code given below right after MIDDLEWARE_CLASSES :

MIDDLEWARE = [
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
]

Will look like this:

change like it and keep the both ke MIDDLEWARE_CLASSES and MIDDLEWARE classes

 MIDDLEWARE_CLASSES = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    # 'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

MIDDLEWARE = [
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',  
]

If you have a custom middleware, try to import it in manage.py shell. Sometimes Django can blame other middlewares when it cannot import yours (because of not installed dependency for example).