Server Version#: Version 1.16.3.1402
Player Version#: Version 4.16.4
Well here is a thing !
Whilst trying to fix an issue of poster art not showing, I set up 2 identical libraries, Both point to the same files, on the same drive. Both libraries report different movie quantities.
One shows 1 less movie, so :-
Movies has 1 more movie and 114 duplicates
Movies2 has 1 less movie but 116 duplicates
how can this be ? both settings are the same for both libraries.
With bad naming, everything is possible!
See: https://support.plex.tv/articles/naming-and-organizing-your-movie-media-files/
What makes you think my files are named incorrectly ? Have you taken a look or something ?
LOL, and neither Ninja’s nor Plex has access to your libraries, so it was a simple guess, based on the amount of duplicates. But yes, granted that they also could be caused by actually having diff. resolutions of same movie etc.
Thats exactly why I have duplicates. Different formats, bitrates and cuts, The question is why do two libraries that point to the same source(s) with the same settings index different results.? They should be the same.
And as said, could still be caused by bad naming
So whats the ones that differs named?
Sorry I don’t understand your question.
You have one movie, that get’s detected differently, correct?
So what’s the name of the directory it’s in, as well as the name of the file it self
I don’t know, There seems to be no way of telling, I am going by the numbers at the top of the screen. Before I made my library I split all the content in to individual directories for file format, and created individual libraries for each, and checked the file count against indexed content, and all was good. After then making one big library by adding all the directories, and duplicating that library I now have a discrepancy between the two. Its not a major discrepancy but I am curious as to why.
Edit :- also a few content that was matched in library 1 with posters and descriptions are not matched in library 2 (although the file is picked up). I am wondering if this is an error in plex with large libraries,
Try this:
Thanks, I had not heard of that - will look in to it.
In the meantime I have discovered that library2 has mis identified The film ‘The Dark Tower’ as a duplicate of ‘The Dark’.
Both are clearly named, but both are .mp4 files. I checked the metadata with a program called MataZ. The film ‘The Dark’ had the correct metadata, however ‘The Dark Tower’ had no metadata at all. So I have corrected that and a rescan.
TBH the filenames are correct, and library1 did not make this error. I would like to know how plex scrapes files, and wonder if its an error in server/server communication. What think you ?
Are the primary agent for both libraries the same?
Also, have you in the past done a “Fix Match” and perhaps there either selected something different from original, or used another source?
And again, most mismatches are due to bad naming, or LMA agent picking up metadata tags in the file itself, especially in MP4 files
Both agents are the same, I don’t remember if I used fixed match or not (its been a while). What I do know for sure is that the metadata was correct for one, and missing for the other, I have sorted that now. A rescan did nothing. Do I have to delete the libraries and remake them to force a proper scan ?
Selecting “Refresh all Metadata” will issue a re-download, but if you also wanna start with a match, it’s fastest to delete library, and then re-add.
And take it you didn’t try WebTools yet?
No not yet, My wife keeps stopping me from doing what I want to do. Just got back from shopping, so will take a look right now.
Ok installed it… It says
Perfect! Media files are present and accessible for all items in the Plex database.
Perfect! All media files are present in the database.
Any idea ?
This means, that all your medias are matched and part of Plex.
As such, we are back to bad naming 
All I can suggest now, with the amount of medias and amount of duplicates, is to extract a list using this:
And please read the manual, before using it, and you can install it easy via WebTools UAS
I’ll have a look at it - sounds like something serious so will heed your warning!.
FWIW this is the first time I have installed plugins.
I have had partial success, I was able to identify the files that were matched as duplicates when they were not. These files were 
Anna (2013) & Mindscape (2014) - identified as Mindscape
The Dark (2018) & The Dark Tower (2017) as The Dark.
God knows why as the files are nothing alike. The only similarity is that Anna and The Dark Tower had no metadata, but the file name should have been enough.
These file are mp4. I have moved them to a directory, run MetaZ on them, and will add them as a library in its own right, and see what the results are.
If so, also check metadata tags in the file them self
I assume your older library has grown organically, while the other was a test where all content was added at once, right?
Sometimes, it even makes a difference if all files are added at once or if they are added in separate library scans. Movies with similar titles tend to get merged more often if they are added in one swoop together.
