Which DLNA server program were you using? Was it Samsung AllShare, Samsung Link, Plex, Microsoft or another?
I have never had any issues with the Samsung servers.
My Samsung Smart TV model UE46H7005 is unable to play a lot of my Mpeg2 video files from my DLNA server. It claims that the audio codex is not supported, but this seems not to be a correct message as the audio format is the same for mpeg2 files actually working. Copying the files to a USB stick did not solve the problem. So I converted the files to Mpg4 format (using Nero Recode 2014) and then the files would play from my USB stick. but still not from my DLNA server.
Samsung support was not willing to look into these problem, so I searched for a solution on the web.
The solution for playing mpg4 files via DLNA was just to rename the file extension to .avi instead of the .mp4 extension.

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