Q: Photos for Mac stuck importing photos from iPhone

I recently upgraded to Photos for Mac from Aperture. Upgrading the library went fairly smoothly. On my first attempt to import photos from my iPhone 6, Photos is now stuck in the import process.

The import tab (device selected) shows the following:

• Already imported (2,509 items)
• New items (442 items)
• No thumbnail images are visible (just the default grey squares indicating items)
• At the top of this screen is an import progress bar that has not shown any progress. This progress indicator says "Importing 442 items" but the bar itself remains grey; I'm assuming there would be either a black or colored indicator showing some progress when the import process is working correctly.

After about an hour with no indication of progress, I selected the "Stop Import" option, with no noticeable results. I tried clicking the Stop Import button several more times, still with no results. Let things be for about five minutes, with no change in status. The import still seems stuck; clicking the stop button does nothing.

Next, I quit the Photos application. An error sheet appears: "Do you want to continue importing? Photos is currently importing files. If you quit the import task will be canceled." I select "Quit".

Now Photos gets stuck closing the library. All app windows close except for a tiny square that says: "Closing the library..." The library does not close and I run out of patience waiting for it to do so and force quit the application.

I am using a 27-inch late-2009 iMac

8GB memory

2.66 GHz Intel Core i5

177GB storage space available

Photos 1.0

Photo library is approx. 107GB