It is always frustrating to see a numeric error code; The “4302” error when opening Photos for macOS is as opaque as most others. Some readers have seen this code when copying Photos to their Mac says it can’t open the Photos Library. Others, when they have slowdowns with Photos or see blurry previews.
In most cases, the answer appears to be that macOS 11 Big Sur does not support, or at least is not fully supported, with a photo library located on an external drive formatted for Windows compatibility using ExFAT. You can check if that’s the case by selecting the drive in the Finder and choosing File> Get Info. In the Format field, it will read ExFAT.
Fortunately, the solution appears to be straightforward, although it requires having enough disk capacity to reformat the ExFAT disk:
- Copy everything from the ExFAT drive to another drive and make sure you have everything.
- Start Disk Utility, (which is in Applications> Utilities) and select the unit in the sidebar. (If you don’t see the drive, select View> Show all devices.)
- Warning: this step is destructive and irreversible. Click Erase.
- In the dialog that appears, enter a drive name, select APFS from Format menu, and GUID partition map from the Scheme menu.
- Click Erase. Disk Utility will format and partition the drive and mount it.
- Copy the old contents of the drive to the new drive.
- Hold down the Option key and launch Photos.
- From the Choose library menu, click Other library and browse to your photo library on the newly reformatted drive. Select that library and click Choose library.
You should go back to normal.
If this fails, exit Photos and hold down the Command-Option key while launching Photos. Click Fix When prompted. This can take a long time.
If that fails too, you may have an irretrievably corrupted photo library, but you can still get your source media back unmodified. This Mac 911 column from 2017 is still accurate for the method to recover those files.
This Mac 911 article is an answer to a question posted by Macworld reader Miguel.
Ask Mac 911
We’ve compiled a list of the most frequently asked questions, along with answers and column links – read our super FAQ to see if your question is covered. If not, we are always looking for new problems to solve! Please email yours to [email protected] Block.com, including screenshots as appropriate and if you’d like your full name to be used. Not all questions will be answered, we do not respond to email, and we cannot provide direct advice for troubleshooting.