PIL: DLL load failed: specified procedure could not be found
I had this problem as well with Python 3.6. I just avoided the problem by uninstalling pillow (4.1.0) and then installing an older version of pillow (4.0.0). It seems to run okay with the older version.
As in Sean's answer, I had to uninstall (I'm using Anaconda Python 3.6, BTW) with
conda uninstall pillow
I tried it with PIL, but there was no such package. Uninstalling pillow also meant uninstalling packages that depend on it, in my case "anaconda-navigator" and "scikit-image". After I reinstalled Pillow 4.0.0 with
conda install pillow=4.0.0
and tested it with
python -c "from PIL import Image"
which, if successful, you don't see an error message, I reinstalled the packages that were uninstalled along with Pillow 4.1.0.
conda install anaconda-navigator
conda install scikit-image