I can't open my external Photo library "unable to open library "4302"

Hi

Unfortunatly that is not a compatible format:

It must be formatted APFS or MacOS extended (journaled) (preferred for spinning drives)

It Must not be (or have been) used for time machine. (A time machine drive can be used if re-formatted)

It must have the 'ignore ownership" checkbox ticked.

It must be directly connected (No ethernet or wifi)

See

https://support.apple.com/en-gb/HT201517

The problem with incompatible volumes is they can work - until they don't. Operating the library on one can result in a gradual build up of errors in the library until it eventually stops opening, otherwise malfunctions, or a later OS version decides it can't work with it. To be honest it is ridiculous that the app doesn’t detect an incompatible volume, and refuse to work with it (with appropriate message) until you sort it out.

I've now seen three separate people with the porblem that 11.5 won't open a library on an ExFAT format drive. You will need to move the library somewhere else (already formatted APFS or MacOS extended), while you re-format the drive to APFS using disk utility (reformatting will erase the contents of the drive). If this means you need to buy a new external drive to have somewhere to put it while you reformat, then it will be easier to first reformate the new drive to APFS, then put the library on the new drive, and use it from there.

I ran into the same problem after upgrading to Mac OS 11.5.1 a few days ago. My Photos library (1.2 TB) was on a SanDisk SSD that was formatted with ExFAT. I solved the problem by (1) copying the Photos library from my SanDisk SSD to a temporary storage device, (2) reformatting the SanDisk SSD with APFS file format, and (3) copying my Photos library back to the reformatted SanDisk SSD. Everything is working fine so far.

I still have thumbnails not showing up after editing a photo, but I think that is a separate issue.

If the format is not APFS or MacOS extended, then it absolutely is the format. Apple has long documented that libraries must be stored on one of these formats.

I've had 3 or 4 people report back with exactly this problem on 11.5.1, who said that when they moved the library to a compatible format that the problem was solved (just look back over the last week or so, with a search for 11.5.1).

The problem with incompatible volumes is they can work - until they don't. Operating the library on one can result in a gradual build up of errors in the library until it eventually stops opening, otherwise malfunctions, or a later OS version decides it can't work with it - as seems to be the case here.

I suspect Apple now have decided not to allow photos to open a library on an incompatible volume to avoid that risk of damage.

A good move in my opinion, (though if that is the case an appropriate error message would be helpful):

See

https://support.apple.com/en-gb/HT201517

After 2.5 hours on the phone with Apple Support, the end solution is the one that you have mentioned. I had to purchase a new external drive, format it to MacOS extended (journaled) and transfer all the files (including the iPhoto Library) from the (LaCie) ExFAT drive that I've used for the last 1.5 years to the new drive. I was then able to run the Photos app, with all the photos that I had.

The Photos program now works fine. It seems that 11.5.1 doesn't work with the iPhoto library file when it's on a drive formatted ExFAT. I'm not so happy with this solution as it cost me the price of a new HD, but the silver lining is that the new drive is faster and larger - leaving me more space for the future.

Hi

The most likely cause is that the format of your LaCie drive is not compatible with a photos library. It needs to be MacOS extended, or APFS.

What is it? You can check by clicking on the drive and hitting CMD-i

You have to format a different drive to APFS or MacOSExtended, and then copy all your files to that drive. It should be fine then. I spent a couple hours on the phone with Apple Support and that was the only solution.

The problem is likely the formatting of your drive. MSFAT won't work anymore. Here is a link: https://support.apple.com/en-us/HT201517

Yes, IF the library is able to be opened once moved to a compatible volume. If the library is too badly damaged, and Photos is not able to repair it, there is a risk that it will still not be possible to open it.|

If that is the case you willl be left with recovery from your most recent backup.

Please also make sure you take a backup of the library as it is now before stating any moves/reformats/repairs. You are working with a lot of data, and all those operations will take some time, with a risk of data loss while they are ongoing.

I also had the very same problem - with the Photo Library on my LaCie external drive that was working flawlessly until I upgraded to Mac OS 11.5.1 a couple days ago. It seems that all the other files which I have on the same external drive are fine. I have difficulty thinking that there are problems with the drive, or the formatting. The change was the OS upgrade. I think there must be a problem with OS 11.5.1 and the Photo Library.

What format are these external drives?