HiΒ @Astghik,
Here is my client's file which she tried to upload yesterday to my website http://velesna.com/o/dz-3-tsit/ and to your websiteΒ http://wpdiscuz.com/addons/wpdiscuz-media-uploader/#comments
Both tries were unsuccessful and she received yesterday this error on your website
.
Here I attach the file which my client couldn't upload on the website.Β
So, it means that there are users (not all but some of them) who can't upload from there computers or phones to any website with Media Uploader add-on.Β
What can be the issue and what to do?
Thank you!