With version 2.5.1 and version 2.5.2 it is not possible to delete an empty folder with the file manager. No problem with Version 2.4.6.

The error message is either:
- Internal Server Error
- Fatal error: Call to undefined method WFJoomlaFileSystem::countFolders() in C:\wamp\www\0J343\components\com_jce\editor\extensions\filesystem\joomla.php on line 366 (posted on http://www.sarki.ch/jce/forum/problemes-divers/9375-mise-a-jour-jce-2-5-2-a-eviter#10738)

I tested on a server that is a difference between HTTP and FTP user on a server that is not the difference, the problem is same.

Thank's
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