How to overcome 'Coudn't find that formation' error when adding web dynos to Heroku django app?

Question

I'm trying to get deploy a simple django app, and have successfully pushed my git repository to Heroku. However, when I attempt to run:

heroku ps:scale web=1 

I get the following error

Scaling dynos... failed  !    Couldn't find that formation. 

Any thoughts as to what the problem might be? The contents of the Procfile (below) are correct to the best of my knowledge.

web: gunicorn my_app_name.wsgi 

Answer 1

To state the obvious: another way to encounter this issue is if you're working on a new app, and you try running heroku ps:scale web=1 before you've actually done a git push heroku master. There is no Procfile on the Heroku server in that case, because there aren't any files at all. :D