Error while uploading PDF on Joomla 3.3.6

I have error while uploading with my latest Joomla 3.3.6 website
I can't use dropfiles
I tried on a 2.5 Joomla website with the same pdf and it works well
alla parameters are ok for the pdf (extension, maximum size)
my website has to be online today and no answer from the ticket support. I'm really ennoyed.
Somebody can help ?

Asked Feb 16, 2017

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