Final Cut Pro 12 - Library is damaged

[latenitefilms]

Apple Feedback Assistant ID: FB21950978

DESCRIBE THE BUG:

Last night I was working on a MASSIVE Final Cut Pro library for a big event, and I got a “library is damaged” error - however it still seemed to work fine. Logs, screenshot and library attached.

Apple responded with:

What is your external media setup information?
What is the drive format? Is the external media folder backed by any cloud storage like Google Drive / iCloud Drive?

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SCREENSHOTS:

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SPECS:

• 2021 16-inch MacBook Pro (M1 Max, 64GB RAM, 8TB SSD)
• macOS Tahoe 26.2
• Final Cut Pro 12.0.0

[latenitefilms]

Reported on FCP Cafe Discord:

[joema4]

I encountered this error on 12.0 a few days ago. I examined the library internals using SQLPro, and the ID (column name ZIDENTIFIER in the schema) was not present in any table. Yet for it to print that ID, you'd expect it to exist somewhere.

I checked each CurrentVersion.fcpevent database plus CurrentVersion.flexolibrary. That is consistent with the report of it being cache-related. I could not reproduce it.

All media and the library were on the internal system SSD of my M1 Ultra Mac Studio, macOS Tahoe 26.3.1. It was a very small test library. I was only testing bug FB10578973 / #109 "FCP video noise reduction produces incorrect frame cadence on retimed rate conformed clip."

I tried OPT+Clip>Verify & Repair Project on each project, and it found nothing.

Due to the transient nature, this is a difficult thing to pursue. It was late at night, and I didn't think to do a "log show" for the previous few minutes.

If anyone encounters this, they can immediately run this command to gather the unfiltered macOS log for the previous 10 minutes. If they zip that and send it to me at the URL below, I can analyze it.

sudo log show --info --debug --style syslog --last 10m > ~/Documents/LogShow_FCP_Error_10m.txt

https://www.dropbox.com/request/MD6p23QwVaY0Ltd0pvMv

In the meantime, I'll examine the conditions under which that error is raised. There is a series of ValidateAndRepair methods that check various things.

[latenitefilms]

Process:             Final Cut Pro [3492]
Path:                /Applications/Final Cut Pro.app/Contents/MacOS/Final Cut Pro
Identifier:          com.apple.FinalCut
Version:             12.0 (445223)
Build Info:          ProEditor-44000005223000000~3 (3E222)
Code Type:           ARM-64 (Native)
Role:                Foreground
Parent Process:      launchd [1]
Coalition:           com.apple.FinalCut [2474]
User ID:             502

Date/Time:           2026-03-12 09:22:08.5216 -0700
Launch Time:         2026-03-12 08:54:20.7023 -0700
Hardware Model:      Mac13,1
OS Version:          macOS 26.3.1 (25D2128)
Release Type:        User

Crash Reporter Key:  A2F28739-D4BD-B1D6-588E-2BC326EE1E60
Incident Identifier: CA707C01-EF39-4C78-A8ED-3D627DB01C17

Time Awake Since Boot: 2200 seconds

System Integrity Protection: enabled

Triggered by Thread: 0, Dispatch Queue: com.apple.main-thread

Exception Type:    EXC_CRASH (SIGABRT)
Exception Codes:   0x0000000000000000, 0x0000000000000000

Termination Reason:  Namespace SIGNAL, Code 6, Abort trap: 6
Terminating Process: Final Cut Pro [3492]


Application Specific Information:
abort() called


Application Specific Backtrace 0:
-[FFAnchoredTimelineModule(FFTLKDataSource) handlerWillStartTracking:]
-[FFAnchoredTimelineModule(FFTLKDataSource) handlerWillStartTracking:]
-[FFAnchoredTimelineModule(FFTLKDataSource) _beginTemporaryTransaction]
-[FFUIAction beginWithUndoState:]
Volume Adjustment
-[FFChannelChangeContext willSetChannel:flagsOnly:]
-[FFChannelAction lockChannels]


Thread 0 Crashed::  Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib        	       0x1898b95b0 __pthread_kill + 8
1   libsystem_pthread.dylib       	       0x1898f3888 pthread_kill + 296
2   libsystem_c.dylib             	       0x1897f8850 abort + 124
3   Flexo                         	       0x10b8c417c -[FFApplication reportExceptionOnTerminate].cold.1 + 76
4   Flexo                         	       0x10acb6f48 -[FFApplication reportExceptionOnTerminate] + 28
5   Final Cut Pro                 	       0x102891094 -[PEAppController applicationWillTerminate:] + 284
6   CoreFoundation                	       0x189989494 __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148
7   CoreFoundation                	       0x1899edf54 ___CFXRegistrationPost_block_invoke + 92
8   CoreFoundation                	       0x1899ede98 _CFXRegistrationPost + 436
9   CoreFoundation                	       0x189967f94 _CFXNotificationPost + 740
10  Foundation                    	       0x18bb926d0 -[NSNotificationCenter postNotificationName:object:userInfo:] + 88
11  AppKit                        	       0x18e30dbc0 -[NSApplication terminate:] + 1580
12  LunaKit                       	       0x103271cac -[LKApplication terminate:] + 84
13  Flexo                         	       0x10acb6ed8 -[FFApplication terminate:] + 484
14  Flexo                         	       0x10aa41d60 Observers::Notify((anonymous namespace)::Notification const&) + 328
15  Flexo                         	       0x10aa41bb0 +[FFNotificationCenter postNotification:] + 148
16  Flexo                         	       0x10aa41e38 +[FFNotificationCenter postNotificationName:object:userInfo:] + 60
17  Foundation                    	       0x18b1be634 __NSFireDelayedPerform + 372
18  CoreFoundation                	       0x1899a119c __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 32
19  CoreFoundation                	       0x1899a0e5c __CFRunLoopDoTimer + 980
20  CoreFoundation                	       0x1899a09d4 __CFRunLoopDoTimers + 280
21  CoreFoundation                	       0x18999177c __CFRunLoopRun + 1816
22  CoreFoundation                	       0x189a4bf3c _CFRunLoopRunSpecificWithOptions + 532
23  HIToolbox                     	       0x1964fc790 RunCurrentEventLoopInMode + 316
24  HIToolbox                     	       0x1964ffab8 ReceiveNextEventCommon + 488
25  HIToolbox                     	       0x196689b64 _BlockUntilNextEventMatchingListInMode + 48
26  AppKit                        	       0x18e2ae014 _DPSBlockUntilNextEventMatchingListInMode + 236
27  AppKit                        	       0x18ddabe48 _DPSNextEvent + 588
28  AppKit                        	       0x18e872f08 -[NSApplication(NSEventRouting) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 688
29  AppKit                        	       0x18e872c14 -[NSApplication(NSEventRouting) nextEventMatchingMask:untilDate:inMode:dequeue:] + 72
30  AppKit                        	       0x18dda4780 -[NSApplication run] + 368
31  LunaKit                       	       0x103272cf0 LKApplicationMain + 228
32  Final Cut Pro                 	       0x102857f08 main + 832
33  dyld                          	       0x189529d54 start + 7184