mac photo

Hold down the option key while starting photos. The resulting pane should list all the libraries on your system. Open each in turn to find the correct library with your photos in.

You might have a failing hard drive. I strongly suggest running Etrecheck as I mentioned earlier.

Have you run any "cleaning apps" like CleanMyMac?

The deafult location of the photo library on mac is located in path /Users/[username]/Pictures  (where "[username]" is your short user account name).

You can find where your photo library is located by opening the Photos application and pressing Preferences in the menu bar. Ones there, you'll want to click "Show in finder". Here you'll find the current location of the library in finder "form". From here it's as simple as dragging the folder into its correct location (mentioned at start).

I had a simular issue before, where the photo library folder was is the wrong location, and this fixed it for me.

Hope this helps. Let me know if it worked or not, and if you have any additional questions, I'm here to help.

How many libraries were found? Just one? or did you get this error on multiple libraries?

It might be worth your while starting your mac in safe mode and then trying.

Use the spotlight in Finder, though if they are in a library, they might be hidden from the finder.

Narrow your search results on Mac – Apple Support (AU)

Hard to say. Sometimes it is easy to drag something without intending to.

Oh, and the number of things on your desktop has *nothing* to do with the speed of the machine.

If you would like get etrecheck from etrecheck.com, run it and post the results in a forum specific to your computer. Someone may see something to help speed up your computer.