Since the change from the old app to photos many of my old videos and photos are missing or corrupt. This is really horrible some of these are my son's birth photos and other important moments. I really lost trust in this software...
MacBook Pro 14″, macOS 14.2
"Since the change from the old app to photos many of my old videos and photos are missing or corrupt. "
Do you mean this happened, when you switched from iPhoto to Photos?
iPhoto needed the old iLife system frameworks to play older videos and process older image formats. Some of the formats, that iPhoto could handle, are no longer supported on the more recent system versions since macOS 10.15 Catalina, when Apple stopped supporting 32bit software. You may want to check the format of the videos that can no longer be played, also the file format of the images, that Photos cannot handle.
See this list for legacy formats for iMovie: About legacy media in iMovie for macOS - Apple Support
Video formats that iMovie can no longer play are probably also problematic in Photos.
I suggest you try to export the videos, that no longer play, with "File > Export > Export unmodified original". If Photos can export the video, try to covert it to a different format. Try the free HandBrake or GraphicConverter, if you already own it.
This will not help with files that are truly missing, but may help with apparently corrupted media, if it is just a problem of a legacy format.
"Since the change from the old app to photos many of my old videos and photos are missing or corrupt. "
Do you mean this happened, when you switched from iPhoto to Photos?
iPhoto needed the old iLife system frameworks to play older videos and process older image formats. Some of the formats, that iPhoto could handle, are no longer supported on the more recent system versions since macOS 10.15 Catalina, when Apple stopped supporting 32bit software. You may want to check the format of the videos that can no longer be played, also the file format of the images, that Photos cannot handle.
See this list for legacy formats for iMovie: About legacy media in iMovie for macOS - Apple Support
Video formats that iMovie can no longer play are probably also problematic in Photos.
I suggest you try to export the videos, that no longer play, with "File > Export > Export unmodified original". If Photos can export the video, try to covert it to a different format. Try the free HandBrake or GraphicConverter, if you already own it.
This will not help with files that are truly missing, but may help with apparently corrupted media, if it is just a problem of a legacy format.
Please read the following user tip and restate your question/problem in detail:
Writing an Effective Apple Support Communities Question - Apple Community
When did this happen? After your upgrade to Sonoma?
Where is the library located? If on an external drive how is the drive formatted and connected to your MBP?
Is it a "managed" or "referenced" library?
Do you have iCloud Library enabled? If so do you also have "Optimize Mac Storage" enabled?
old photos and videos are missing from my library
