This post has NOT been accepted by the mailing list yet.
Plex Server Not finding a MP4 video- Solved!
This article shows you three easy ways to fix MP4 to Plex issue, you can take it as reference.
Plex Media Server is a sophisticated media management program that takes your entire collection of movies, music, and still images and presents it in a slick and navigable package. It is officially stated that MP4 is supported by Plex. However, sometimes you will find it's unable to add MP4 files to Plex server or even Plex doesn't find/recognize the MP4 files. In fact, Plex media player can only play MP4 with the codec H.264 or MPEG-4. However, MP4 is a format container with different codecs and Plex can't detect some MP4 files with other codecs. If you want to play a video or an audio in Plex media player you must ensure that the video or audio codec is one from FFmpeg codecs. So we need convert MP4 to Plex media player supporting formats, such as, MPEG-2 video codec, DTS audio, AC3 audio codec.
There is a smarter way to get rid of the incompatibility issues quickly. Simply convert the MP4 files to MP4 or MKV files with codec H.264 or MPEG-4. Along with some help from third party program like Dimo Video Converter Ultimate, it is professional on fast transcoding MP4 to Plex Media Server with H.264 or MPEG-4 MP4 format (the most compatible video format for Plex) without quality loss. In addition, it not only supports MP4 videos, but also handles various common video formats, like MXF, VOB, MOV, MKV, AVI, WMV .etc. For Mac users, Dimo Video Converter Ultimate for Mac is also a helpful app to encode videos for further usage.