Emgu.CV 3.4.1.2976 "Could not load file or assembly"

This is a bit of a strange one.

I'm building a module for an existing C# ASP.NET web app that will generate thumbnails from a video file; I've been trying different options to see what works best.

I started with Emgu.CV 3.4.1.2976, installed from NuGet. Everything worked fine, and I was able to generate a thumbnail from a video.

I went on to install various other products (MediaToolkit, AForge, Accord, VideoUltimate) that purportedly to the same thing but none of them worked properly out of the box like Emgu.CV; so in uninstalled all of them except Emgu.CV.

At that point Emgu.CV started giving me this error when I tried to run the code:

Could not load file or assembly 'Emgu.CV.World, Version=3.4.1.2976, Culture=neutral, PublicKeyToken=null' or one of its dependencies. A strongly-named assembly is required. (Exception from HRESULT: 0x80131044)

I literally changed NOTHING about Emgu.CV - not the package, not the references or "using"s, not even the thumbnail code which worked at first. It worked out of the box after I installed it, but after installing and removing some other packages, it gave me the above error. I also did not change anything about the containing solution and project other than installing and uninstalling packages with NuGet.

I can't for the life of me figure this out. I have since tried uninstalling Emgu.CV completely and then re-installing it; but no dice - still gives me the error.

Any ideas?

Never mind; I never did get 3.4.1.2976 working again, but I solved my issue by downgrading Emgu.CV to version 3.2.0.2721 in NuGet.