Single.php showing blank page - php

Question

I'm trying to build a theme of my own and uploading it to Wordpress, but my single.php file it's not working at all. It's just showing a blank page. I've tried so many things to get it to work, but now I don't know what to do anymore. This is my php-file for the blog page:
<?php
/**
*Template Name: Blog Posts
*/
get_header('header4'); ?>
<section id="headerbox">
<header>
<h2 class="referensrubrik">Nyheter</h2>
</header>
<p class="referenstext">Det senaste från AL Konsult.</p>
</section>
<main id="blog">
<?php // Display blog posts on any page # http://m0n.co/l
$temp = $wp_query; $wp_query= null;
$wp_query = new WP_Query(); $wp_query->query('showposts=5' . '&paged='.$paged);
while ($wp_query->have_posts()) : $wp_query->the_post(); ?>
<article id="blogpost" id="post-<?php get_the_ID(); ?>" <?php post_class(); ?>>
<h2><?php the_title(); ?></h2>
<h5><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></h5>
<?php the_excerpt(); ?>
<hr>
</article>
<?php endwhile; ?>
<?php if ($paged > 1) { ?>
<nav id="nav-posts">
<div class="prev"><?php next_posts_link('« Previous Posts'); ?></div>
<div class="next"><?php previous_posts_link('Newer Posts »'); ?></div>
</nav>
<?php } else { ?>
<nav id="nav-posts">
<div class="prev"><?php next_posts_link('« Previous Posts'); ?></div>
</nav>
<?php } ?>
<?php wp_reset_postdata(); ?>
</main>
<?php get_footer(); ?>
Now my single.php just looks like this (I've tried the loop, but it's just not working...):
<?php
/**
* The Template for displaying all single posts.
*/
get_header('header3'); ?>
<section id="headerbox">
<header>
<h2 class="referensrubrik">Rubrik</h2>
</header>
<p class="referenstext">Text</p>
</section>
<?php
error_reporting(-1);
?>
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
<h1 class="entry-title"><?php the_title(); ?></h1>
<div class="entry-content">
<?php the_content(); ?>
</div>
</article>
<?php endwhile; ?>
<?php get_footer(); ?>
What am I doing wrong!?

Answer 1

I fixed it! The single.php code that works for me looks like this:
<?php
/**
* The Template for displaying all single posts.
*/
get_header('header3'); ?>
<section id="headerbox">
<header>
<h2 class="referensrubrik">Rubrik</h2>
</header>
<p class="referenstext">Text</p>
</section>
<?php
$post = $wp_query->post;
while ($wp_query->have_posts()) : $wp_query->the_post(); ?>
<article id="blogpost" id="post-<?php get_the_ID(); ?>" <?php post_class(); ?>>
<h2><?php the_title(); ?></h2>
<h5><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></h5>
<?php the_content(); ?>
<hr>
</article>
<?php endwhile; ?>
<?php if ($paged > 1) { ?>
<nav id="nav-posts">
<div class="prev"><?php next_posts_link('« Äldre inlägg'); ?></div>
<div class="next"><?php previous_posts_link('Nyare inlägg »'); ?></div>
</nav>
<?php } else { ?>
<nav id="nav-posts">
<div class="prev"><?php next_posts_link('« Äldre inlägg'); ?></div>
</nav>
<?php } ?>
<?php wp_reset_postdata(); ?>
<?php get_footer(); ?>

Answer 2

Your template tag is outside of the block.
<!-- /*
Template Name: Blog Posts
*/ -->
<?php
It should be:
<?php
/*
Template Name: Blog Posts
*/

Answer 3

Make sure there are no blank spaces or carriage returns outside the tags (especially in WP page templates): The spaces/carriage returns will cause the page not to render by throwing an exception (which you are likely not seeing because you dont have reporting enabled).
Specifically I am referring to this:
<!-- /*
Template Name: Blog Posts
*/ -->
It needs to be inside the opening PHP tag, and there should be no empty lines at the top of the page.
It should look like (no empty line breaks):
<?php
/**
* The Template for displaying all single posts.
*/
require_once('../../../wp-load.php');
get_header('header3'); ?>

Answer 4

Remove the following line from your code:
require_once('../../../wp-load.php');