Connection Reset when port forwarding with Vagrant

1). Project must be run as python manage.py runserver 0.0.0.0:8000.
if this is not fix your problem then

2). Open your Vagrantfile and add
config.vm.network "forwarded_port", guest: 8000, host: 8001 this after
# config.vm.network "forwarded_port", guest: 80, host: 8080 line

This work in my case ;)

Note: This forward port info provided when run vagrant up
....
==> default: Forwarding ports...

default: 8000 => 8001 (adapter 1)
default: 22 => 2222 (adapter 1)

I had Django listening on 127.0.0.1:8000 (default)

As explained in Mitchell's answer here: Vagrant's port forwarding not working I should have been listening on 0.0.0.0. Here is a quote of his answer:

I wanted to add an additional note that often this is caused by the server within the VM because it binds to 127.0.0.1, which is loopback. You'll want to make sure that the server is bound to 0.0.0.0 so that all interfaces can access it.

If you're using Django, you want to start the dev server like this: ./manage.py runserver 0.0.0.0:8000