Only protocol 3 supported

问题

I try to configure Django with PostgreSQL on Windows 10. When I run server usually I get an error

only protocol 3 supported

but sometimes the server starts properly.

I installed 32-bit Postgres 9.6 and psycopg2 2.7.1.

In settings.py I have

DATABASES = {
 'default': {
  'ENGINE': 'django.db.backends.postgresql_psycopg2',
  'NAME': 'postgres',
  'USER': 'django',
  'PASSWORD': 'django',
  'HOST': 'localhost',
  'PORT': '5432',
 }
}

Do you know any solutions for the problem?

来源：https://stackoverflow.com/questions/44881827/only-protocol-3-supported