The Akonadi personal information service is not operational

I get this error when I open Kmail.
I have upgraded to the latest version of Manjaro

Try from terminal:
rm -r ~/.local/share/akonadi/
and restart KMail.
Or make a backup of that folder … so you might keep some of the older data …

It worked.
Thanks.

What was stored in that folder?
I did make a backup.

I can’t actually recall, not using any akonadi related stuff anymore, but some of the files seem to get corrupted somehow, on some particular circumstances.

Must have been some settings. Had to set my default trash folders and sent folder in Kmail again.