Why isn't my image texture working? I am currently using blender 2.8 and I was putting a texture on a plane, so it shouldn't have to be unwrapped, but it crashed and when I went to put it back on it just comes out as like an average color value of the image rather than the actual image. I have saved and quit, tried different images on new shaders. Nothing. In the screenshot showing image texture should be marble, but instead it's a bright white, it isn't a scaling or lighting problem.

Also worth noting that I'm using cycles to render.

Many Thanks
Have you Unwrapped That Plane again because as i think this happens only when Plane is not Uv Unwrapped just go to top view and in the edit mode just hit 'U' and then hit 'Project from View' 
come back to object mode
and also connect the texture coordinate and mapping node to the image texture
This Should Work For You