Books MIA after Calibre v3 Upgrade

[mazeckenrode]

After upgrading to Calibre v3, none of the books that were already in my library under the previous version show up now. I’ve verified that all the books are still where they’re supposed to be on my hard drive, and that Calibre does in fact recognize that location as my Calibre library. Why doesn’t Calibre show these books, and how do I fix it?

[kovidgoyal]

https://manual.calibre-ebook.com/faq...libre-is-blank

[mazeckenrode]

Thank you, and sorry that I missed that in the FAQ. I have now had Calibre restore the database, however it has done so with the error message “The following folders were ignored” returned for seven of my books, without giving an explanation why.

[ableal]

Originally Posted by mazeckenrode

[..] with the error message “The following folders were ignored” returned for seven of my books, without giving an explanation why.

Well, I just had this happen to me for one book. Long story short, make the
"calibre_id" number in line 4 of the metadata.opf match the number in the book folder.

I.e., if the folder is "Clever Book Title (1234)", line 4 of the metadata.opf file inside should be:
<dc:identifier opf:scheme="calibre" id="calibre_id">1234</dc:identifier>

Worked for me (TM).

----

Long story: I was fixing a library synced across several machines, one of the sync agents had quit and some changes were not properly propagated (not Calibre's fault, of course). After fixing a couple dozen duplicate ids (renames failed to propagate), there was one "The following folders were ignored" warning. The problem may have been there before, not sure.

Google found me very few results for that error message: basically this thread, and the source code at https://fossies.org/linux/calibre/sr.../db/restore.py. I think that the restore function compares the id encoded in the folder to the one in the metadata.opf file, and in case of mismatch throws the error:

[...]
194 mi = parsed_opf.to_book_metadata()
[...]
200 if int(mi.application_id) == book_id:
[...]
211 self.mismatched_dirs.append(dirpath)
[...]

earlier:
98 ans += 'The following folders were ignored:\n'
99 for x in self.mismatched_dirs: