Quote:
Originally Posted by theducks
Either way would show that (### selected on the status bar)
All those are legitimate 'Empty Books',. So someone told Calibre to delete Formats for those books.
With the Highlight mode ON (as you were), this would leave you mostly unaware the multi books were selected, when you really intended to remove it from only 1 book. Always check the STATUS LINE at the bottom 
You can Drag and drop an actual book format i(from your backup-Archive) into the Details pane or into the Metadata Edit window for that book, leaving the covers and metadata intact  Use care, you can drop ANY book there, it does not check that it belongs  |
For what its worth. No one has deleted any of those books. I'm the only person who handles the library and probably haven't deleted more than a handful of books and never more than one at a time. I always look at the popup to be sure I am only deleting one. Moreover, the books are still in the Calibre folder and not deleted.
Thanks for all the help and suggestions. Given the number of books and time involved it will be some time before I get around to fixing it if I ever decide to take the time. In the meantime I will just manually copy them when I want to read them.
Let me know if there is an easier way but it appears I can move the books that are visible to Calibre to a new library. Prior to that I need to create a list of the 472 so that I can add the formats back to the new library. The only way I know of to create a list is to take multiple screenshots as I scroll through them. Then doubleclick or drag and drop each book to the Calibre app?