lost my custom columns while changing computers

[cigale]

Hello!
I was using Calibre on a previous computer and had a bunch of custom columns - one for wordcount (using a wordcount extension), one for fandom (I download fanfics to my Kobo using the FanFicFare extension), another for Kobo collections.

When I changed computers, I downloaded Calibre again. All of my documents, including my Calibre library, are in the cloud (mega.nz - kind of like dropbox I guess) so my books all automatically appeared in my new Calibre, but without the columns. When I went to export data from my old Calibre, the columns and extra info was all gone from the old Calibre.

Is there any hope of getting that info back?

I did backup my entire Calibre library prior to changing computers. So I've tried copying the backup on to my old computer and putting all the books back into my old Calibre that way, but the columns are still missing. I'm not sure if the info is gone, or if it's still there but the program doesn't know how to get to it anymore.

Any advice? Thank you!

[theducks]

custom columns are part of the metadata.db of the library they were created IN.
It sounds like you ADDED the books again (and the books do not auto generate a column that is not present, even if the metadata managed to get embedded)

*IF* there was a metadata.db aready in your cloud archive, just start over (the local) and COPY ALL the files+folders from your cloud Library into the new Library folder

[cigale]

Thanks! That's super helpful.

I copied the metadata.db folder from my backup onto my old computer, and now the columns (and the data) are back on my old Calibre. Which is very reassuring! But once I opened my new Calibre and went to add books from the cloud (the cloud automatically copied them onto my new computer, so I just went to add books and picked the local folder where my books were located), they are gone again.

Is there a better way to copy everything over from my old computer?

I saw something somewhere about exporting data, is that what I should be doing instead of just copying the folder from one computer to the next?

I also tried copying on the metadata folder directly to my new computer, but that didn't do anything.

Thanks again!

[Bookstooge]

Since you are using the cloud, I highly recommend you read this warning straight from the manual:

https://manual.calibre-ebook.com/faq...rked-drive-nas

[dunhill]

You should also have saved the Calibre settings.
Found in preferences / Miscelanea open the Calibre configuration directory.
You copy the files from that folder and paste them on the new computer

[cigale]

Amazing! I stopped the cloud storage, that must have been why I kept losing everything. And I transferred over the files from the Calibre configuration directory and everything looks great now - my columns and my extensions are back! Thank you for all the help!