I recently udgraded my iMac to macOSMonterey and cannot find my Photos Library, how can I recover them?

hold down the option key while starting photos, and see if your old library is listed then. If it is, open it.

Were you using iCloud to sync your photos (If you were, and all your photos are in iCloud then an alternative to the suggestions below is simply to let Icloud sync to a new empty Library - it will take some time, possibly days and you need to keep photos open while it does it)

If not:

Open finder, and look in your pictures folder. What libraries are in there? (Normally somthing.photoslibrary). If there is more than one of those, you probably need the largest. Open it from the "other library" button above.

3 - If that doesn't help then you are going to need to do a search in spotlight.

In finder, in the search bar, type "photoslibrary". Make sure it is searching "This Mac"

What does it find?

By default - that is, unless you moved it - your Photos Library is in your Pictures Folder. Is it?

And, just in case, you made a back up before upgrading, of course...

Again - where are these libraries you are trying to open currently stored. If on an external drive, are they one of the compatible formats (APFS or MacOS extended - with the ignore ownership bit set)

We really need to know the file system format of the external volume. The error message number 4302 you quoted "The library could not be opened. Foto's-bibliotheek.photoslibrary (4302) " is very common for keeping the Photos Library on a volume with an incompatible file system format. The format should be either MacOS Extended (Journaled) or APFS, and on no account ExFAT or similar.

You can do a finder spotlight search for "Photos" or "Library" and see if it can be found.

You might look in the trash.

An upgrade to Monterrey should not disturb any user files.

Hi

One drive is a networked/synced drive. Your other library is on an ExFAT drive. Neither of these locations are compatible with a photos library and tend to cause exactly the sort of problems you are seeing.

You need to move the libraries to a drive which is compatible. Formatted APFS, or MacOS extended, and directly connected (internal, USB or thunderbolt) not networked (no wifi, no ethernet and no synced drives such as dropbox)

If you have enough space on your internal mac drive, try putting them in the pictures folder.

Photosarchive is just the name of my external hard drive. Yours will be called something different - whatever it was named when purchase or formatted. The screenshot is there to show you how to check the format of your drive. (select the drive and hit CMD-i.

When you get these error messages, are you opening a library on your external ExFAT drive?

Is that on an external drive.

If so, is it APFS, or MacOS extended, and directly connected to your mac (USB or thunderbolt - no network). If not, then it is not compatible with a photos library.

Or if it is in the trash it needs to be dragged out to access it.