WD Ultra - "some files failed to backup"; What files?

I backup nightly to a 1 TB external drive. Backups running fine until last few days. My notifications are:
Backup Complete 6/15/2017 6:31:56 PM
Backup Started 6/15/2017 6:00:07 PM
Some files failed to backup 6:15/2017 8:10:47 AM + (button that shows VIEW)

The backups have been starting at 6:30 PM and ending at approx 6:30 PM for months now.

I have no idea what it is trying to do at 8:10:47 AM??? If I click on the view button it just shows the Current backup plan. I have no idea what files are not being backed up or what files are not. Why can’t we get a backup LOG???

Hello,

What’s the name of the backup software and what operating system are you running on your computer?

Windows 10, upgraded from windows 7.
WD Backup Version 1.5.5953

WD Backup has been running since April 13, 2016 on Win 7 and then the upgrade to Win 10 without any issues until a few days ago when I got the notice about files not being backed up. Now it is running OK again. I don’t know why it had an issue or why the issue went away.

There is no log at all! No error log, no completion log. When the software failed I don’t know if it missed one file or all the files.Guess you just have to “hope” it is working! Don’t even know how many files are backing up.