SOLVED: Jellyfin server crashes consistently during library scan (~24%) after upgrade

[JayisonJellyfin]

After upgrading Jellyfin from 10.7 to 10.11, the server consistently crashes during library scans at around 24–25% progress.
Initially, the web client still showed version 10.7 even though the backend service was updated to 10.11, so the database migration did not run at first.
Eventually, I was able to trigger the correct migration and get the web UI to match 10.11 after deleting the Jellyfin cache folder, but the issue with library scans persists.

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System setup

• Previous version: 10.7.x
  
• Current version: 10.11.x
  
• Platform: Windows (service install)
  
• Media path:
  \\DS1522\Volume 1\Media Backup
  (Synology NAS share)
  
• Database and cache: default local paths
  
• Browser/Web UI: now correctly shows 10.11
  
• Plugins: all uninstalled during troubleshooting (Fanart plugin was crashing early in the process)
  

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Problem summary
After the upgrade, the web interface initially didn’t update and migrations didn’t run. Once the cache was cleared, the migration to 10.11 completed successfully and the UI version matched the backend.
However, the library scan still crashes Jellyfin service at ~24% completion, regardless of settings or file changes.
The crash occurs without a clear stack trace — the log typically ends after:

[INF] Main: Prepare system for possible migrations
[INF] Jellyfin.Database.Implementations.Locking.NoLockBehavior: The database locking mode has been set to: NoLock

followed by an abrupt stop in the service.

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Steps taken so far

1. Upgrade process
   • Manually upgraded Jellyfin from 10.7 → 10.11.
     
   • Confirmed service binary was 10.11, but web interface still showed 10.7.
     
   • Migrations were not triggered automatically.
     
2. UI version fix
   • Deleted Jellyfin’s cache folder.
     
   • Restarted service → web client updated to 10.11, and migration completed.
     
3. Plugin cleanup
   • Uninstalled Fanart and all other third-party plugins (Fanart was initially crashing).
     
   • Restarted the server with only official/default components active.
     
4. File integrity checks
   • Ran PowerShell scripts to validate image files across the media library.
     
   • Found and isolated corrupted .jpg and .trickplay files into a quarantine folder.
     
   • Confirmed no remaining invalid image files in the library.
     
5. System/network checks
   • Verified NAS connectivity and read/write speeds (stable).
     
   • Disabled Windows Defender and real-time scanning.
     
   • Confirmed no permission or path issues.
     
6. After cleanup
   • Rebooted both NAS and Windows host.
     
   • Tried rescanning with all metadata disabled.
     
   • Still crashes at ~24% each time.
     

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Current status

• Jellyfin backend and UI both now correctly on 10.11.
  
• All non-core plugins removed.
  
• Cache rebuilt and corrupted image files quarantined.
  
• Database migrations completed successfully (post-cache deletion).
  
• Service still crashes at 24% during library scans.
  
• Event Viewer shows no specific application error related to Jellyfin.
  

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Expected behavior
The media scan should complete successfully, or at least fail gracefully with an error message rather than crashing the service.

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Actual behavior
The Jellyfin service stops completely during the scanning process around 24% progress, without detailed errors or trace logs indicating the failing component.

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Looking for guidance on

• How to enable the most detailed trace logging to identify which item triggers the crash.
  
• Whether a partial or re-initialized metadata database could resolve this.
  
• If there’s a way to force a clean reindex without wiping existing metadata.
  
• Whether the earlier version mismatch (10.7 UI / 10.11 backend) may have left partial schema corruption.
  
• Any known issues with Fanart or migration leftovers in 10.11 that can cause library scan crashes.
  

I'm trying to upload my debugging logs but I can't seem to do that here.

edit: I've uploaded the logs to github https://github.com/jellyfin/jellyfin/issues/15207

Thanks guys

[JayisonJellyfin]

I rescanned every single library one by one and eventually narrowed it own to a specific library. After checking the logs, it turned out Jellyfin was trying to probe video files listed inside old .nfo metadata files — but those filenames no longer existed (the videos had been renamed). This caused repeated ffprobe failed errors and eventually a crash.

Fix:

Moved all metadata files (.nfo, .xml, .json, .jpg, .png, .zip) out of the problematic library folder.

Removed the affected library from Jellyfin.

Re-added it clean, without any of the old metadata.

Ran a full library rescan — it completed successfully.

If your scans consistently stop partway through, check for stale or mismatched NFO files. Cleaning them out and letting Jellyfin rebuild fresh metadata fixed the issue completely.

[Leeward]

Fix:
Moved all metadata files (.nfo, .xml, .json, .jpg, .png, .zip) out of the problematic library folder.
Removed the affected library from Jellyfin.
Re-added it clean, without any of the old metadata.
Ran a full library rescan — it completed successfully.
If your scans consistently stop partway through, check for stale or mismatched NFO files. Cleaning them out and letting Jellyfin rebuild fresh metadata fixed the issue completely.

Thank you for this! It's looks like a partial solution to my server shutdown issue. I found couple of .nfo, and .xml files. No .json or .zip. there are image files all over, so I left those alone. Didn't delete the library, but metadata scans ran to completion. I may go back and do the library re-add.

[John Hill]

Thank you for this post!
I just upgraded from a rock-solid 10.10. to 10.11.4 and start having problems.
Just like you mentioned before, at some point during the "Scan All Libraries", the app would just die.

Event Viewer shows the following:
Faulting application name: jellyfin.exe, version: 10.11.4.0, time stamp: 0x68f20000
Faulting module name: unknown, version: 0.0.0.0, time stamp: 0x00000000
Exception code: 0xc00000fd
Fault offset: 0x00007ff822c8b274
Faulting process id: 0x1CF0
Faulting application start time: 0x1DC6BB0917E47AD
Faulting application path: C:\Program Files\Jellyfin\Server\jellyfin.exe
Faulting module path: unknown
Report Id: 15d27387-8457-4565-b109-c6f0b41a58d0
Faulting package full name:
Faulting package-relative application ID:

It is failing somewhere in my library of Audio files.
I just successfully removed, cleaned, and re-added my smaller list of Music files.

Now I am working on my larger set of files... gradually adding to see what fails.