Photos library and macOS Catalina

Well, the newer system isn't compatible with having a Photos library on an NAS server. Others like you ran on that type of server without problem but many soon ran into accessibility problems. It came to a head with Catalina where it is total incompatibility. Aperture was better designed and was much more compatible with referenced files on an NAS server.

An option is to get a small, external SSD drive like one of these: OWC Mercury Elite Pro mini. I have a rotating disk mini and it's not much bigger than a Magic mouse.

Even smaller is using an OWC SSD connect by an SATA to USB 3 adaptor like this one:

The 1 TB SSD is around $135.

I am also having this issue on a 2015 iMac recently upgraded to macOS Catalina. My library is stored on the internal storage "Macintosh HD" and exhibits the same behavior.

Opening Photos to a blank window and an alert that reads "Photos cannot find the System Photo Library named “Photos Library”". Choosing the correct library instantly brings this alert back up with no apparent change. Repairing the library and rebooting the system has no effect.

I have also been signed out of iCloud Photos. Every time I recheck Photos in iCloud settings, it says "Checking Library" for a second or two, then unchecks Photos again as if nothing has happened.

If anyone has any solution, please help us. I cannot find any further troubleshooting advice regarding this problem.

I have the same issue. Seems like my original Photos Library and any new Photos libraries I create have "com.apple.quarantine" attribute set and I could not find a way to remove it. It is not the only issue with Catalina, won't be installing it on a production machine any time soon.

An update for me. The latest macOS Catalina supplemental update 10.15.1 has fixed the core issue of my system not recognizing my photo library.

However, Photos is now in the process of re-uploading my entire library of 19,000 photos to iCloud Photos, which will take a few more days for me. The upload appears to be functioning correctly though.

Hi,

I have the same issue: upgrading to Catalina, and unable to open Photos. Restored the backup with Mojave, issue solved. Made a clean install of Catalina: unable to open Photos. Went back to Mojave. This I repeated 2x.

Apparently I just cannot upgrade to the latest and greatest. Tried everything, restoring, safe modes, repairing, nothing works under Catalina.

Mojave will be my OS until Apple recognised the issue and solves it. Macbook Air, early 2014.

Hi 'Old Tod'. The library is stored on a Synology NAS. The library is about 127GB and having a Macbook Air with the 256GB SSD, makes it necessary to store the photos externally.

This system, I am using for more than 8 year, from iPhoto, to Aperture to Photos. I cannot change this system: the Synology disk is a 2-disk NAS with Miror backup setup. Just to be sure I dot lose the pictures. In fact, a 2nd NAS on an external location is used for a weekly backup from the main NAS... oops, I start to get paranoia I guess...

I have been using a similar setup, although only for about 2.5 years, and since Catalina had many problems with my Photos library. And all I keep reading is “Don’t put photos on a NAS”!

I guess these people delete all their photos and videos?

How is the external HD formatted and connected to your iMac?

It should be formatted as shown in this screenshot an connected by cable:

Sorry, 'Old Toad'... not 'Old Tod'...