Create conda environment: "Found conflicts!" when solving environment and "Finding shortest conflict path" running forever

This error and the subsequent behaviour is very likely coming from the Anaconda bug which from time to time causes inconsistencies in the local environment. As of Jan 26th, 2020 the bug was not yet resolved.

For me the same problem manifests profoundly on Mac.

In general, the answer to this question is that you should create your .yml from hand by scratch, with only the required channels and constraints. You should relax the version constraints so that they only look like 1.19 instead of 1.19.10

However, despite following this advice, I have almost exactly your problem right now. It spent many hours on fontconfig and I left it overnight before giving up. My spec is pretty simple:

channels:  - conda-forge  - usgs-astrogeology  - defaultsdependencies:  - python=3.6  - isis3  - gdal=2.3

I'll edit this when I figure it out.

EDIT: This problem is under discussion here (specific to the software I was trying to set up, probably not helpful for others) https://github.com/USGS-Astrogeology/ISIS3/issues/3570

In my case, I had replaced some of the build versions (the ...=he4413a7_1000 part) as the ones in the original file had been relabelled as broken on conda-forge. However, even though the version number hadn't changed for these dependencies, their subdependencies had changed, causing all these conflicts. The bottom line is: don't mess with dependencies manually.

I solved the problem by keeping the original build version specifications, and adding conda-forge/labels/broken to the channels part of the .ymlfile.