If you attach files to a topic, then the files are applied perfectly. ( http://sosedi.ml/ru/groups/view/2/topic_id:4 )
When trying to watch or download the files, it turns out the problem.
For example: attached to a topic PDF file ( AC150401001.pdf )
in a topic on the screen and the file is displayed as PDF
Download or view the file fails. The file is damaged.
Confused yet that when you try to open a file in Firefox, to existing file extension added another extension html
How can I fix it?
Thanks in advance.