Media files manager error: "vmError: Sorry,It's not a valid media file"

[frytako]

Hello to everyone!

A few weeks ago I started a website using Joomla 2.5.8 Stable and virtuemart 2.0.14. In local environment the VirtueMart Media Files manager works just fine (backend - VM - shop - Media Files), but now I uploaded the web online to make some tests and the Media Files manager fails:

I believe that the Media Files paths are set ok, and all the directory permissions in joomla are set to writeable, but when I try to upload Media Files from the backend of VM I always get the error "vmError: Sorry,It's not a valid media file", no matter which file (jpg, mp3...) or role (Displayable,Downloadable or For sale) I'm trying to upload. (see attached file). Trying to upload the same document in local environment works fine.

I also tried to create a new product (online) uploading a new image inside it, and it worked, so I guess that the problem must be with the Media Files manager.

Have you got any idea on what should I try?

Thanks to all and have a good day!!

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