Thread:Project:Support desk/Problems after upgrade of Mediawiki from version 1.19 to 1.23.3

I recently completed an upgrade of our intranet MediaWiki installation and our users are now reporting an issue with multi-user simultaneous/concurrent editing of different sections.

Users will receive the edit conflict error message when they are editing different sections/subsections of a wiki page. Any help regarding how to troubleshoot or resolve this would be greatly appreciated.

$wgDiff3 is pointing to the correct location in LocalSettings.php. Is there another var or setting that needs to be added/removed?

MW 1.23.3 PHP 5.3.6 MySQL 5.5.21