The following may help some...
Issue: MP4 files incorrectly categorized and wrong year/date value displayed when viewed in DLNA client (in my case Windows Media Player and Roku Media Player). Year/date value for media file showing as xx-xx-2036 or xx-xx-1902.
Reason: Twonky appears to pull the year/date used to categorize and display on screen (via DLNA client) from the "encoding date" or "tagging date" (per MediaInfo). Mediainfo (http://mediaarea.net/nn/MediaInfo/Download) shows encoding/tagging date of the affected files as 2036-xx-xx.
Suspected Cause: It appears the wrong date was either introduced by Handbrake under certain instances or was carried over from source file (possibly FLV) used when converting with Handbrake to MP4. This wrong encoding/tagging year/date only occurred with a few files, most files converted with Handbrake converted correctly.
Solution: The solution is to use FFMPEG (https://www.ffmpeg.org/download.html) to copy the video file and inject a new media creation date/time. Note this copy will strip out some of the extended metadata including album artwork. That metadata and artwork will have to be re-added after file is copied and new creation date/time is injected. The steps below will allow one to change multiple file to the same encoding date/time, or one at time by editing the file after each conversion. One simply drags the video file onto the ".bat" file to begin the copying process.
Caution: These are general directions, use them at your own risk!!! It is recommended to make backups of the files just in case.
1) Copy affected video files to local computer.
2) Create a ".bat" file (on Windows, use Notepad). Type or copy the following code adjusting the FFMPEG file location as needed:
[full file path to FFMPEG executable]\ffmpeg" -i %1 -vcodec copy -acodec copy -metadata creation_time="2015-11-17 12:00:00" "%~n1.remux.mp4
3) Save file to the same directory as the video files on local computer. Make sure to set the file extension to ".bat".
4A) To change a single video file's encoding date/time, edit the ".bat" file creation_time text between the quotes to the desired date and time, save the ".bat" file. Then select the file and drag it over the top of the ".bat" file and release. A command window should appear detailing the copying process and will disappear when copy process has completed.
5A) If copy was successful a new file appended with "remux" that is similar in size to the source file should have been created.
4B) To change multiple video files so they all contain the same encoding date/time, edit the ".bat" file creation_time text between the quotes to the desired date and time, save the ".bat" file. Then select each individual video file and drag them, one at a time, over the top of the ".bat" file and release. A command window should appear detailing the copying process and will disappear when copy process has completed.
5B) If copy was successful new files appended with "remux" that is similar in size to the source file should have been created.
6) The file(s) can now be renamed to remove the appended "remux" text. Note: May have to rename or remove source file prior to renaming new copied file. Note: See Metadata below to add or edit metadata prior to next step.
7) Copy the video files back to the My Cloud and check with DLNA client if video files have been corrected and are playable. In certain cases one may have to access the My Cloud Dashboard, navigate to Settings > Media > DLNA Media Server then select Rebuild. Twonky will rebuild the media database. Database rebuild may take some time if there are a large number of media files. In certain instances one may have to reboot the WD My Cloud before the DLNA client will reflect the updated Twonky database.
Metadata: The copy process may strip out certain metadata from source file. If this is the case use a free metadata tagger like MP3Tag (http://www.mp3tag.de/en/download.html) or MediaMonkey (http://www.mediamonkey.com/download/) to add, fix, change, correct the file's metadata. This includes adding or removing "album artwork" that will be displayed as the video file icon or image. MediaMonkey has the option to pull tagging data from online sources.
Note if using MediaMonkey: In certain instances MediaMonkey incorrectly tags the Title tag for MP4 media files resulting in the DLNA client to display "[data]" as the title for the MP4 video file. And in certain instances MediaMonkey will incorrectly tag the "content" field as "podcastdesc". In both cases use MP3Tag to fix these error. Simply resaving the MP4 video file with MP3Tag will fix the title "[data]" error. In MP3Tag, right clicking on the MP4 video file and selecting "Extended Tag", then editing the "podcastdesc" entry and changing it from "podcastdesc" to "comment" and then save the changes.
File created, modified, accessed date and time: If the media file's created/modified/accessed date/time is not acceptable or if you want to change those values one can use a free program like file_date_touch.exe" (http://date.bghot.com/download.php) to modify the created/modified/accessed date and time of files. Note: There may be a bug with the "file_date_touch.exe" program where the hour is one hour advanced from the hour set with the program. If this is the case set the hour to one hour prior to hour desired.