Loading Windows 10 DLL. "This operation is only valid in the context of an app container"

I am currently working on a native plugin for Unity involving other static libraries (dependencies). I have recently upgraded to Windows 10, and am running the most current Unity. I followed instructions and dropped my dll in the Plugin's folder within Assets, but when running in editor I get the error in the title. The dll fails to load and subsequent calls to imported methods gives me "file not found ". Here is my local c# referencing the dll: public class video : MonoBehaviour { public string videoName; public string folder; public bool isPlaying; [Range(0.0f, 100.0f)] public float videoTime;

     public delegate void FrameCallback(int id, IntPtr data, int width, int height);
     public FrameCallback frameHandler;
 
     [DllImport("ffmpegForUnity")]
     public static extern int initVideo(string name, string folder);
     [DllImport("ffmpegForUnity")]
     public static extern int setFrameCallback(FrameCallback fn);
     [DllImport("ffmpegForUnity")]
     public static extern void getVideoFrame();
 
     public struct Frame
     {
         public int id;
         public byte[] data;
         public int width;
         public int height;
     }
     Frame mFrame;
 
     // Use this for initialization
     void Start () {
         //set up video context
        initVideo(videoName, folder);
         frameHandler = new FrameCallback(FrameHandler);
         setFrameCallback(frameHandler);
     }

and the header file for my dll:

 #ifdef FFMPEGFORUNITY_EXPORTS
 #define FFMPEGFORUNITY_API __declspec(dllexport)
 #else
 #define FFMPEGFORUNITY_API __declspec(dllimport)
 #endif
 
 extern "C"
 {
 #include <libavcodec/avcodec.h>
 #include <libavFormat/avformat.h>
 #include <libswscale/swscale.h>
 #include <libavutil/avutil.h>
 }
 
 using FrameCallback = void(*)(int id, uint8_t* data, int width, int height);
 FrameCallback mFrameCallback = NULL;
 
 namespace ffmpegForUnity {
     class  videoHandler {
         
         public:
             static FFMPEGFORUNITY_API int initVideo(char* video, char* folder);
             static FFMPEGFORUNITY_API void* getVideoFrame();
             static FFMPEGFORUNITY_API bool setFrameCallback(FrameCallback callbackMethod);
     };
 }

Has anyone run into this before? Googling has not helped. I found one other problem and the solution was to run the unity application in a visual studio simulator, but I want my plugin to be able to be used on multiple platforms, not just in the windows store.