ErwinS

I did not use this plugin. The themes on which this occurred were all custom made and fairly old.

Hi,

Thanks for the reply.

Indeed the Bauhaus theme was active, which was correct since no other theme was available. After some further investigation it turned out the problem was the “old” pro version. Although it was not active it was still present on file-system. I was triggered by the option “Settings” on the deactivated plugin on the Plugins-screen to remove the old plugin files. This solved the problem of the Fatal error.

Regards,

I found out that if in your theme in functions.php “add_themesupport(‘post_thumbnails’)” is set post_parent is also correctly set. Will test this on several other themes as well.

After some debugging I noticed “wp_print_media_templates” has been changed since WP3.8.3. If I now add {{ data.postId }} to the header “Drop files anywhere to upload” for uploading images I get an empty response on 3.9, although on 3.8.3 I still get the ID of the main-post (parent). This happens with and without WordPress SEO enabled. Can someone explain how a new attachment is linked to a post on WP3.9? This will help me searching for a sollution. Thanks.

I detected which plugin breaks the post-parent. Unfortunately it happens after enabling wordpress-seo plugin. Also if this plugin is the only active plugin post_parent is still set to 0. Although this does not happen with twentyfourteen. So I will investigate my custom theme.

Thanks in advance