My customer sitting in a local government office has the problem, that he cannot use the filemanager anymore (two weeks ago all was fine). The filebrowser shows no files or folders, it stays empty without error message.
The joomla media manager instead shows all files and folders.
Same problem in a Joomla 2.5 and 3.4 installation, latest JCE and filemanager.

From outside the office filemanager/browser works fine.

Seems to be a firewall problem?
There have been firewall updates.
What does the filemanager need to work?

Best regards
Daniela
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