Hi everyone,
I’m experiencing an issue with local trailers not showing up in Plex, and I’m hoping someone can help me figure out what’s going wrong.
Issue:
Some trailers I’ve placed in the “Trailers” subfolder under the respective movie directory do not appear in Plex. However, this is not a problem with the video files themselves. I have tested this by copying a trailer from a movie where trailers work fine into the folder of a movie where they do not show up. The result: even the working trailer does not appear when placed in the problematic movie’s “Trailers” folder.
I have noticed this issue with six movies so far, including:
• Beverly Hills Cop (1984)
• Brother Bear (2003)
• The Bourne Conspiracy
The videos are encoded in HEVC MP4 format and play fine on my computer. All were created using the same software and settings.
Movies structure:
Movies/
├── Movie Name (YYYY)/
│ ├── Movie Name.ext
│ ├── Trailers/
│ │ ├── Movie Name (Trailer 1).mp4
│ │ ├── Movie Name (Trailer 2).mp4
│ ├── Shorts/
│ ├── Scenes/
What I’ve Tried:
• Ensuring trailers are named correctly (with -trailer suffix or using subfolder).
• Copying known-working trailers into the non-working folders (they do not appear there either).
• Checking file permissions.
• Restarting Plex and refreshing the library.
• Searching the forum for similar issues, but found no solution.
Questions:
• Has anyone encountered this issue before?
• Could there be a metadata-related problem causing Plex to ignore certain trailer folders?
• Are there any logs or debugging steps I should check to understand why these specific trailers are not being detected?
• Any other suggestions?
• If you are experiencing the same issue, please comment so we can gather more data.
Any help would be greatly appreciated! I can provide logs or sample files if needed.
Let’s maybe start with the simple things… did you refresh the movie’s metadata after adding the trailer video? Local extras are picked up by the metadata agent, not the file scanner.
If that’s not it… which agent do you have configured for this library (Manage Library > Edit... → Advanced)
Yes, I did refresh the metadata for each affected movie after adding or changing the trailer files (both via the “Refresh Metadata” option on the individual movie and by refreshing the whole library). Unfortunately, the trailers still do not show up for these specific titles, even though the same trailer files work fine in other movie folders.
It’s important to note that this issue only affects a small number of movies—trailers are detected and displayed correctly for the vast majority of my collection. This makes me think it’s not a general user error or misconfiguration.
As for the agent, I’m currently using the Plex Movie agent for this library (confirmed under Manage Library > Edit > Advanced).
To provide more context:
I have already tried a complete fresh setup—uninstalling Plex Media Server, deleting all configuration files, and creating a brand new database from scratch. Even after this full reinstallation, the exact same movies still do not have their trailers recognized, while trailers for all other movies show up as expected. The folder structure is identical for all movies in my library, so there’s no difference in how the files are organized between the working and non-working cases.
Additionally, I should mention that I had to rebuild my database some time ago due to a separate issue. Before that, with my previous database (which had been in use for about two years), all trailers—including for these problematic movies—were detected correctly. It was only after I was forced to rebuild the database from scratch that Plex stopped recognizing trailers for these specific titles. Since then, no matter what I try (including further fresh installs and new libraries), the exact same movies are affected, while all others still work fine.
This pattern suggests the problem might be related to changes in how Plex scans or matches media after a database rebuild, rather than the file structure or the trailer files themselves.
If you have any ideas or need more details, I’m happy to provide them!
I recently discovered the root cause behind an issue I had with local trailers not showing up in Plex: the overall file path length.
What I Found:
Some trailers placed in the “Trailers” subfolder under a movie’s directory were not showing up in Plex. After some thorough testing, I confirmed that Plex does not recognize trailers if the total file path exceeds a certain length. This is not related to the file format or content – the same trailer files work when placed under a shorter path.
My trailer files typically follow this naming pattern:
Movie Title (English Trailer 1).mp4
So, if the movie folder name is already long (e.g., due to including {edition-Extended}), and the trailer name is descriptive, the total path length can easily become too long and Plex silently skips the file.
Example structure:
Movies/
└── A Very Long Movie Title with Additional Descriptors {edition-Extended} (2020)/
├── A Very Long Movie Title... (2020).mp4
└── Trailers/
└── A Very Long Movie Title (English Trailer 1).mp4 ← Not recognized
Once I shorten either the folder name or the trailer file name, the trailer shows up again in Plex as expected.
I’ve also seen a similar limitation when using Pre-roll videos in the cinema trailer setup – so this seems to be a broader restriction on path length for local extras.
Feature Request:
I’d like to kindly request that the Plex team consider increasing the maximum file path length for:
Local extras (trailers, scenes, shorts, interviews, etc.)
Pre-roll cinema trailers
This is not a bug in the traditional sense, but the current path limitation significantly impacts usability – especially for users who maintain clean, descriptive library structures.
Why This Matters:
Better support for long or detailed titles (e.g., box sets, director’s cuts)
Greater flexibility and robustness in library management
Avoids silent failure (trailers don’t show up, no warning or error)
Thanks for all the great work so far – this small improvement would make a big difference!
Following up on my previous post about trailers not being recognized when the file path is too long, I’ve made a more specific discovery that may help narrow down the cause of the issue.
What I’ve Found:
It turns out that it’s not necessarily the length of the trailer filename or the movie folder name that causes Plex to skip the trailer – but rather the length of the movie file’s name itself.
Example:
This setup does not work (trailer not shown):
Very Long Movie Title (2020)/
├── Very Long Movie Title {edition-Extended}.mp4
└── Trailers/
└── Very Long Movie Title (English Trailer 1).mp4
This setup does not work (trailer not shown):
Shorter Movie Title (2020)/
├── Very Long Movie Title {edition-Extended}.mp4
└── Trailers/
└── Very Long Movie Title (English Trailer 1).mp4
This setup does work (trailer shown):
Very Long Movie Title (2020)/
├── Shorter Movie Title {edition-Extended}.mp4
└── Trailers/
└── Very Long Movie Title (English Trailer 1).mp4
Why This Matters:
The total path length still seems to be the key factor.
However, reducing only the movie filename (without changing the trailer filename or folder name) resolves the issue.
This suggests that the limitation might be triggered specifically by the movie file’s full path, including its filename.
So, if someone is running into this issue and can’t shorten their trailer names or folder names (due to naming conventions), shortening the movie filename itself can be an effective workaround.
Request:
If this behavior is due to a hardcoded limit in Plex, I’d like to kindly ask the team to consider increasing this path length threshold – or at least document it clearly so users can avoid the problem more easily.
I wanted to provide an additional finding related to my previous reports about trailers not being recognized in Plex. After more testing, it seems that the problem is not strictly about path length as I originally thought, but rather about special characters in the movie filename – specifically German umlauts (Ä, Ö, Ü).
What I Found:
If the movie filename itself contains an umlaut (e.g., Ä, Ö, Ü), then Plex will not display any of the trailers in the Trailers subfolder.
The movie folder namecan contain umlauts without causing any issue.
The trailer filenames themselves may also contain umlauts without issue.
The deciding factor is only the movie file’s name.
Example:
Not Working (trailers not recognized):
Movie with Ü (2025)/
├── Movie with Ü (2025).mp4 ← Umlaut in filename → breaks trailer detection
└── Trailers/
└── Movie with Ü (Trailer 1).mp4
Working (trailers recognized):
Movie with Ü (2025)/
├── Movie with UE (2025).mp4 ← Replacing Ü with UE fixes the issue
└── Trailers/
└── Movie with Ü (Trailer 1).mp4
Notes:
So far, this issue only appears when the main movie filename contains an umlaut.
Trailers and folders are not affected.
This makes it hard for users with large German-language libraries to keep consistent naming conventions.
Request:
I don’t know if this is a parsing limitation or a bug in the way Plex handles filenames with certain characters, but it would be great if support for umlauts (and similar non-ASCII characters) in the movie filename could be improved.
So far, there hasn’t been any response to my earlier findings, so I don’t expect a quick fix. But I hope this detail might help clarify the problem and possibly get it on the radar.
In case you are doing this:
Do not group different editions/versions etc of the same movie into an overall subfolder for that movie title.
Sticking more closely to the naming rules is more important when trying to use local extras.
Also: local extras cannot be shared among different editions of the same movie.
As for the Umlaut-issue: I am suspecting this is an effect of the interplay of the file system on your NAS and MacOS.
If there is a way to define the local character set that’s used by the NAS, try setting it to something different than it is now.
If you are using SMB file sharing, try switching to NFS.
I do not use overall subfolders for multiple editions. Each edition is in its own folder, e.g., Film 1 (2024) {edition-Extended} and Film 1 (2024) {edition-Uncut}.
Plex runs on macOS, while the media is stored on a NAS and accessed via SMB. However, SMB can be excluded as the cause because renaming files directly on the NAS via DSM yields the same result.
Temporary workaround I found:
Before renaming all files:
Rename the movie file without umlauts.
Refresh library and metadata.
Rename the file back to its original name with umlauts.
Refresh library, but not the metadata.
This preserves the trailer, but only as long as the metadata for that entry isn’t updated again (including during automated maintenance).
Not perfect, as automatic updates are often desired.
Removing/replacing umlauts entirely also works but doesn’t reflect the original movie title.
The problem in detail:
Trailers in the Trailers folder are not displayed if the movie filename contains German umlauts (Ä, Ö, Ü, ä, ö, ü, ß). This seems independent of the folder name or trailer filename – only the movie file’s name matters.
What I tried:
Normalizing filenames with NFC/NFD to ensure consistent Unicode representation.
Using the Unicode “modifier” for colons (U+A789 ꞉), similar to how Plex handles colons.
Copying files directly to the Mac and renaming them there.
Using SMB and NFS shares to see if the protocol affected results.
Observations:
Plex still fails to recognize the trailer if the movie filename contains umlauts, even after normalization.
The issue persists even without SMB – renaming files directly on the NAS has the same effect.
Removing or replacing umlauts with ASCII equivalents (e.g., Ü → UE) is currently the only reliable way to get Plex to detect trailers.
Other characters, like colons, can be preserved using Unicode variants (e.g., ꞉), and Plex recognizes them.
Possible causes:
Likely an interaction issue between Plex on macOS and the NAS filesystem, probably related to character encoding.
SMB itself is not the culprit.
Potential solutions / suggestions:
For now, renaming movie files to replace umlauts with ASCII equivalents works reliably.
Plex could improve support for Unicode characters in filenames, especially German umlauts.
Providing an option to define character encoding for local files could solve this without renaming.
It’s tricky because users often want to keep the original movie titles intact, but Plex currently cannot handle umlauts in filenames for trailer recognition.
Has anyone found a better workaround, or can the developers consider improving Unicode handling for local extras?
I don’t see how that is a valid test.
I’d still say try using NFS. That is a UNIX thing.
Linux on your NAS and MacOS are both UNIX-descendants.
Using a Windows-based file sharing protocol in this constellation doesn’t strike me as well-suited.
I’ve noticed that Plex on macOS fails to recognize local trailers only for movies whose filenames contain German umlauts (Ä, Ö, Ü, ä, ö, ü, ß).
Interestingly:
TV shows are unaffected – trailers work correctly there.
Folder names and trailer filenames don’t matter.
This strongly suggests that the problem lies within Plex itself, specifically its movie scanner on macOS, rather than the filesystem, SMB/NFS, or NAS setup.
For now, the only reliable workaround is to replace umlauts with ASCII equivalents in movie filenames.
I’ve actually tested NFS. The trailers are recognized correctly with NFS – however, it causes bigger problems:
Some movies are no longer displayed in Plex at all.
Special characters, like in “Beverly Hills Cop – Ich lö̈s’ den Fall auf jeden Fall”, cause entries to disappear.
My entire library got scrambled, and I had to restore from a backup.
For me, NFS is definitely not a viable solution. I’ll stick with SMB for now and temporarily remove umlauts from movie titles so that Plex can detect the trailers.
Interestingly, umlauts work perfectly fine for series, including trailers. This strongly suggests that the issue lies within Plex itself – probably a difference in how movie and series libraries handle filenames. With proper support from Plex, umlauts could also work reliably for movies.
