Mac Photos app disconnects from image file locations.
Mac Photos app disconnects from image file locations. Message says "The volume for “IMG_0001.CR2” cannot be found. Connect the disk or mount the server volume needed, then try again", or "Missing file: Photos with unavailable original files cannot be opened. The original photo “IMG_0204.CR2” is either offline or cannot be found. Click “Find Original” to reconnect". The disk is an external USB disk but it is also running the OS so it is not disconnecting. The problem is temporarily fixed by closing and re-opening Photos. I have tried repairing the library and creating a new one, but the issue remains.
iMAc Late 2012, OSX 10.12.6, Photos Version 2.0 (3161.4.140).
iMac 21.5″, macOS 10.12