title: Django LookupError: No installed app with label 'admin'
body: <p>I'm trying to running the appserver with python manage.py runserver with python 3.8.2 and django 3.0.3. I've setup a mysql database connection and inserted my "myApp.apps.myAppConfig" into INSTALLED_APPS, declared a couple of database-view based models, a form and a view. Nothing that seems too out of the way for the tutorials i've found. When i run the python manage.py runserver command, this is the output:</p>
  
  <blockquote>
    <p>Watching for file changes with StatReloader Performing system
    checks...</p>
    
    <p>Exception in thread django-main-thread: Traceback (most recent call
    last):   File
    "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py",
    line 155, in get_app_config
        return self.app_configs[app_label] KeyError: 'admin'</p>
    
    <p>During handling of the above exception, another exception occurred:</p>
    
    <p>Traceback (most recent call last):   File
    "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\threading.py",
    line 932, in _bootstrap_inner
        self.run()   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\threading.py",
    line 870, in run
        self._target(*self._args, **self._kwargs)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\autoreload.py",
    line 53, in wrapper
        fn(*args, **kwargs)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\commands\runserver.py",
    line 117, in inner_run
        self.check(display_num_errors=True)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py",
    line 392, in check
        all_issues = self._run_checks(   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py",
    line 382, in _run_checks
        return checks.run_checks(**kwargs)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\registry.py",
    line 72, in run_checks
        new_errors = check(app_configs=app_configs)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py",
    line 13, in check_url_config
        return check_resolver(resolver)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py",
    line 23, in check_resolver
        return check_method()   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py",
    line 407, in check
        for pattern in self.url_patterns:   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py",
    line 48, in <strong>get</strong>
        res = instance.<strong>dict</strong>[self.name] = self.func(instance)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py",
    line 588, in url_patterns
        patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)   File
    "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py",
    line 48, in <strong>get</strong>
        res = instance.<strong>dict</strong>[self.name] = self.func(instance)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py",
    line 581, in urlconf_module
        return import_module(self.urlconf_name)   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\importlib__init__.py",
    line 127, in import_module
        return _bootstrap._gcd_import(name[level:], package, level)   File "", line 1014, in _gcd_import   File
    "", line 991, in _find_and_load   File
    "", line 975, in _find_and_load_unlocked 
    File "", line 671, in _load_unlocked<br>
    File "", line 783, in
    exec_module   File "", line 219, in
    _call_with_frames_removed   File "C:\Users\celli\Desktop\Interventi Comuni\Python\django-projects\zabbixPyFace\zabbixPyFace\urls.py", line
    21, in 
        path('admin/', admin.site.urls),   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py",
    line 224, in inner
        self._setup()   File "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\contrib\admin\sites.py",
    line 537, in _setup
        AdminSiteClass = import_string(apps.get_app_config('admin').default_site)   File
    "C:\Users\celli\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py",
    line 162, in get_app_config
        raise LookupError(message) LookupError: No installed app with label 'admin'.</p>
  </blockquote>
  
  <p>I tried searching big G for answers but there's many sources that can cause this problem, could any of you gurus provide some insight?</p>
  
  <p>Update:</p>
  
  <p>I've already checked the INSTALLED_APPS and django.contrib.admin is present: </p>
  
  <p>INSTALLED_APPS = [ 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', # jupyter notebook plugin 'django_extensions', ]</p>