[Django]-AttributeError at /admin/ by Django 'WSGIRequest' object has no attribute 'user'

Your settings file was created using django 1.9. You are runnig django 2.0

Django 2.0 changed the middleware setting.

To activate a middleware component, add it to the MIDDLEWARE list in your Django settings.

Change

MIDDLEWARE_CLASSES = [...]

to

MIDDLEWARE = [...]