public function validateFeaturedImageUpload($featuredImageUpload) {

        // not acceptable file extension
        if (!$this->isImageFileExtensionKosher($featuredImageUpload)) {
            return "Your uploaded image file, ".$featuredImageUpload.",  is not an accepted image file type.";
        }

        // file already exists on the server
        if ($this->doesImageFileExistOnServer($featuredImageUpload)) {
            return "Your uploaded image file, ".$featuredImageUpload.", already exists on the server.";
        }

        // file upload failed
        if ( ! \Input::file('featured_image_upload')->isValid() ) {
            return "There were problems uploading your image file, ".$featuredImageUpload.".";
        }

        return "passed";
    }