WPML translation issue
In a recent project we’ve run up against a tedious issue with the WPML plugin. WPML is that plugin that allows you to turn WordPress in a pretty powerful multilingual CMS. When clicking on the + icon to add a post or page translation and saving, WPML created a new post or page disconnected from the original.
The “This is the translation of” select was automatically set to “none” and there was no way to change it. After a bit of googling, we’ve found the solution!
Run the following query in PhpMyAdmin:
select * from wp_icl_translations where element_id is null
If you get some results (we got a couple of pages), make a backup of your database (just in case) and remove all the records which resulted from the query above. Then, try again to add a translation and everthing should work perfectly :-)