I had my app working with ImageField via Pillow. An unrelated issue set off an update domino chain and now I am stuck trying to get Pillow to work.

My upgrade to Python 3.6 forced me to upgrade Pillow to version 4, which doesn't seem to work with Django. When I run a check I get:

gallery.Photo.image: (fields.E210) Cannot use ImageField because Pillow is not installed.
HINT: Get Pillow at https://pypi.python.org/pypi/Pillow or run command "pip install Pillow".

Of course I have already done that. I upgraded to Django 1.11, but I am still getting this same error.

I tried adding Pillow to my INSTALLED_APPS, but it was not found. Besides, I hadn't needed to do that before. How can I troubleshoot this issue?

UPDATE: I printed out a list of modules on my virtual environment and I couldn't find Pillow on the list. However, I can see the files in my env directory.

All of the other apps that installed in the same environment with the same pip were listed on the modules readout and when I try to install Pillow again, it tells me the requirement is already satisfied.

I did find an item called pil on the list, but I am not able to uninstall anything called pil or PIL from the env.