IPhoto Library on External Drive and Face recognition

Hi

Is the external drive correctly set up for using with a photos library?

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

It Must not be (or have been) used for time machine.

It must have the 'ignore ownership" checkbox ticked.

It should not be on a memory stick, SD or similar.

It must also not be a network drive (a direct connection is required - eg USB or Thunderbolt).

File sharing services such as iCloud Drive, Drop box, Onedrive etc are not compatible with Photos libraries.

It stands to reason that if you want any sort of reasonable performance it should be a fast drive with a fast connection.

See

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

You can format the drive with Disk Utility, as described here: Erase and reformat a storage device in Disk Utility on Mac - Apple Support

Most drives will come with the wrong file system format, even if the box is claiming "formatted for Mac". This just means, that a Mac can read files on that drive, but does not mean that it is save to store a library there.

If you are getting yourself a new external drive, buy one with enough storage to last for years. The drive should have enough storage to hold at least twice the size of your Photos Library, better even more, because repairing or upgrading the Photos Library will need plenty of extra storage. occasionally you will need to make a duplicate copy of the library, before start with major changes in your library, like weeding out duplicates or similar. then you will need enough storage to create a duplicate on the same volume as a current safte copy.

For a MacBook Air I would get a small portable drive, so it will not be a hardship to keep it connected to the MacBook Air at all times. A drive with your Photos Library needs to be plugged into the Mac, whenever you are signed into your user account, even if you are currently not working with Photos, or the faces scan and other background processes for Photos will never finish.

OK - that disk is not formatted with a suitable format for a photos library. It is ExFat, and needs to be APFS (Or Macos Extended Journaled, but APFS is better for an SSD)

The danger if you don't fix that is your library can become damaged and you lose access to your photos.

The problem is you are going to need to temporarily copy the library to a different drive so you can format it. (Formatting will erase all the contents)

Do you have a suitable drive to copy it to?

Hi

If you can move the library somewhere else while you do it, you can format it using disc utility. Leonie has provided a link above that describes the process.

You don't need a new drive, just re-format the one you have (new drives mostly are not formatted for macs anyway)

If when you've read the article at the link - if there's something you don't understand, get back and one of us will help further.

Also is the library itself on the EHD or just the original source image files and you're running a "referenced" library?

Just launch Disk Utility on your Mac, select the existing hard drive you want to reformat, click on Erase, select OS X Extended (journaled) and then click on Erase again.