Localhost Works Fine but Live Site Generating Header Error

Hmmm, interesting. My XAMPP is running PHP 5.3.8 and my web server is running 5.3.16 but surely it’s highly unlikely something so significant could be the cause?

I appreciate the input bud, but I’ve tinkered and it’s born no fruit.

Any other ideas?

Thanks for that bud, I just tried adding the extra error reporting to my local site, you’re not going to believe this, nothing, no errors it still works perfectly!

The first two errors may be linked to something else, but regardless they’re only warnings, the header error on the other hand is fatal and is what is dragging the site down. Now I understand why header errors are generated, because something is trying to write data to the header after it is already loaded, but I just can’t see how that helps me!

I’ve tried deactivating the plugin and it stops the error, which is both useful and a massive pain as my security structure was built around this plugin! I’ll take your advise and raise a ticket with the dev’s but I’ve never had much luck getting responses from dev’s so if you have any other thoughts please feel free to share.

Thanks for all your help.

Ok, I’ve been digging into this and I think I know exactly what the problem is I just don’t know what to do about it.

It seems you were right I was hasty to dismiss the two notices, as you pointed out they indicate that the $post global is being read as empty. Here is the section of code that’s playing up (note this is from the plugin so not my work, but the dev’s have unanswered tickets from over a year ago):

function check_for_members_only()
	{
		global $post;

		if ( is_admin() ) return;

		// Check for a members only blog
		$blog_is_members_only = get_option( 'wpac_members_only_blog', false );

		if ( $blog_is_members_only && ! is_user_logged_in() ) {
			$redirect_to = get_option( 'wpac_members_blog_redirect', wp_login_url( $_SERVER['REQUEST_URI'] ) );

			if ( empty( $redirect_to ) ) {
				$redirect_to = wp_login_url( $_SERVER['REQUEST_URI'] );
			}

			header( 'Location: ' . add_query_arg( 'redirect_to', $_SERVER['REQUEST_URI'], $redirect_to ) );
			exit();
		}

		if ( get_post_meta( $post->ID, '_wpac_is_members_only', true ) && ! WordPressAccessControl::check_conditions( $post->ID ) ) {
			if ( is_singular() ) {
				$redirect_to = get_post_meta( $post->ID, '_wpac_members_redirect_to', true );

				if ( empty( $redirect_to ) ) {
					header( 'Location: ' . get_bloginfo( 'wpurl' ) . '/wp-login.php?redirect_to=' . $_SERVER['REQUEST_URI'] );
				} else {
					header( 'Location: ' . add_query_arg( 'redirect_to', $_SERVER['REQUEST_URI'], $redirect_to ) );
				}

				exit();
			}
		}
	}

The equivalent for non-members has the same problems. The specific line that is throwing the error is:

if ( get_post_meta( $post->ID, '_wpac_is_members_only', true ) && ! WordPressAccessControl::check_conditions( $post->ID ) ) {

This suggests that you’re right and for whatever reason the global $post is empty so the code cannot run this check.

I’ve tested three scenarios for loading this page, navigating to it works fine, after the refresh has been called (after changing the post url and title) it errors and if you try navigating to it directly it errors.

All of these scenarios work correctly locally.

So this leaves me with a definite problem at least, why is the global empty? But leaves two obvious questions: What do I do about it? Why is it only on live not local?

Any ideas bud?