Debugging WWW

The console and WWW.error message is not providing enough information for me to debug why my app is reading some images and not reading others. I am using System IO FileInfo Class to dynamically scan a folder of images. I read in the file.Name and base in-game variables on that filename. Some images work, but some do not; the two images are right next to each other and both ‘.png’. WWW.error just says “Couldnt Open File: …” If I rename an individual image that can fix the problem, which probably means it’s a logical bug in my code but I’ve been scanning it for hours

//relevent code
fullImgURL = "file:///" + System.IO.Path.GetDirectoryName(Application.dataPath) + "/Assets/Books/book" + bookNum + "/images/" + filename + ".png";
	
wwwInputImage = new WWW(fullImgURL);

		//Apply correct texture
		if(readLeafSide == "FRONT"){ //<-- based on filename
			//Debug.Log("recognized frontside");
			currentLeaf.GetComponent(Leaf).frontSide = wwwInputImage.texture; //does work
		}
		else if(readLeafSide == "BACK"){ //<-- in filename, if I change to FRONT it works 
			//Debug.Log("recognized backside");
			currentLeaf.GetComponent(Leaf).backSide = wwwInputImage.texture; //doesnt work
		}
Debug.Log(wwwInputImage.error); //"Couldn't open file:// ... "

Can I get more debugging info on a www get? I looked into the permissions of the images, they seemed to be the same.

Have you tried running in debug mode using mono develop?

Open your script using mono develop.
Select run/attach and pick the unity instance
Add some break points.
Inspect your variables etc

K