If you’re working with a complicated site then you may find that importing files and posts into WordPress is a bit of a black art – there are lots of places where things might go wrong. If the upload_url_path value for your site has been manually changed, then this might cause problems with WP export files.

Q: why would you change upload_url_path?

A: changing upload_url_path lets WordPress serve images etc. from a subdomain or different domain, which should improve site performance if you have an image-heavy site.

This is an example item entry from the WordPress eXtended RSS export file (this is a simplified entry, with most of the post data (comment status, stickiness, time, post ID etc. removed for clarity).

<item>
	<title><![CDATA[Triplets]]></title>
	<link>https://iso200.com/photo-blog/signs/neon-triplets/attachment/dsc_6318/</link>
	<pubDate>Fri, 15 May 2009 20:20:12 +0000</pubDate>
	<dc:creator><![CDATA[dlf]]></dc:creator>
	<guid isPermaLink="false">http://iso200.com/simple/wp-content/uploads/2009/05/dsc_63181.jpg</guid>
	<description></description>
	<content:encoded><![CDATA[neon, sign, Rue de la Paix, Paris, France]]></content:encoded>
	<excerpt:encoded><![CDATA[Rue de la Paix, Paris, France]]></excerpt:encoded>
	<wp:post_type><![CDATA[attachment]]></wp:post_type>
	<wp:attachment_url><![CDATA[//content.iso200.com/2009/05/dsc_63181.jpg]]></wp:attachment_url>
	<wp:postmeta>
	<wp:meta_key><![CDATA[_wp_attached_file]]></wp:meta_key>
	<wp:meta_value><![CDATA[2009/05/dsc_63181.jpg]]></wp:meta_value>
	</wp:postmeta>
</item>

The problem is with this line:

<![CDATA[//content.iso200.com/2009/05/dsc_63181.jpg

The attachment url line doesn’t contain a protocol – either http or https – which is why my media import failed. A protocol isn’t needed when you change the upload_url_path value – but it is needed when WP is importing media.

Solutions:

1. Post-export: grep the file – add a transport protocol to the url – i.e. http: or https: Don’t forget to add the : after the protocol – the wp:attachment_url line should now look like this:

<![CDATA[https://content.iso200.com/2009/05/dsc_63181.jpg

2. Pre-export: check your media library settings and make sure a protocol is included:

NB: you only see these options in your Media Settings page if you have changed the value of upload_url_path.