Is image 1801 corrupted in some way?
I removed it just in case but the import is still not moving forward.
Why not just import a few folders at a time?
You could then periodically back-up the catalog as well.
If you want the full structure visible in Lr, once you have a folder imported, you can right-click and select 'Show Parent' and repeat as needed
I tried one folder at a time and when I got to 1800 it stopped. I tried importing from an external hard drive and it stopped at 1800.
Is it reporting anything in the logs?
From Applications - Utilities runs Console, in the search box (top right) enter Lightroom and see what the messages (if any) say
There's all sorts of gibberish in there for Lightroom, none of which means anything to me.
Its the messages that start with Lightroom; anything about errors or asset numbers?
Ignore anything like
29/10/2015 19:55:16.589 WindowServer: disable_update_timeout: UI updates were forcibly disabled by application "Lightroom" for over 1.00 seconds. Server has re-enabled them.
29/10/2015 19:55:16.801 WindowServer: common_reenable_update: UI updates were finally reenabled by application "Lightroom" after 1.21 seconds [0.83fps] (server forcibly re-enabled them after 1.00 seconds [1.00fps])
29/10/2015 17:41:12.000 kernel: process Adobe Lightroom caught causing excessive wakeups. Observed wakeups rate (per sec): 996; Maximum permitted wakeups rate (per sec): 150; Observation period: 300 seconds; Task lifetime number of wakeups: 390981
Lightroom 6.2 has major import/export problems. I took the suggestion from Adobe of uninstalling Lightroom and going back to 6.1.1. Finally, all is working as it should.
I don't see anything that's meaningful but there's hundreds of line items.
If you wanted to try an earlier version, a process is described here - http://www.lightroomqueen.com/how-do-i-roll-back-to-lightroom-2015-1-1-or-lightroom-6-1-1/
Or, if you want to persist with trying to find the problem
1. Exit Lr.
2. Restart it
3. Look in console for the new messages from L2, in particular any regarding assets The messages should start with date & time and then Adobe Lightroom
4. Try an import
5. If it fails look at the new messages for any that originate from Lr
After uninstalling LR6.2.1 and loading an earlier version of LR all of my photos loaded on the first try.