[Ersatzreifen]

I had been processing a few hundred books and had to stop to go out of town. While I was gone there was a power failure, and when I returned I discovered that many of the formats were missing. When I click on 'edit metadata' the database still lists the ebooks, but shows the actual files aren't there any more, and the covers are missing too. This happened to random books throughout the database.

When I exited the 'edit metadata' and checked the 'Formats' column, it shows the list of formats as being there - but they aren't.

Next, I selected one of the books and clicked on 'Open containing folder' it contained only the metadata.opf file, the epub and cover file were missing.

Then I went up to the parent directory, (/home/Calibre/Calibre Library/Lynsay Sands/) and found that it contains this tree:

├── Der Teufel und die Lady (28113)
│** ├── cover.jpg
│** ├── Der Teufel und die Lady - Lynsay Sands.epub
│** └── metadata.opf
├── Der Teufel Und Die Lady (28113)
│** └── metadata.opf

There are two directories but should only be one. Calibre is seeing only the directory without the epub and cover files.

I repeated that on a second book and got this:

└── Schwanengesang (28504)
    └── metadata.opf

...and several others which appeared like this:

├── Kryptografie_ Verfahren, Protokolle, Infrastrukturen (28880)
│** ├── cover.jpg
│** ├── Kryptografie_ Verfahren, Protokolle, Infra - Klaus Schmeh.epub
│** └── metadata.opf
└── Kryptografie_ Verfahren, Protokolle, Infrastrukturen (iX Edition) (28880)
    └── metadata.opf

So for most of the books, the files are there, but in a different directory. While I'm writing this I'm making a copy of the entire Calibre library tree on another drive to use as a back up. But what's next? Is there a relatively way to restore all these books? If you need more info just tell me what you need and I'll dig it out as soon as I figure out how.