I’m on a up-to-date openSUSE Tumbleweed. kmail Version 6.8.0 (26.08.1)
Since »Volksverschlüsselung« ended its services, I needed a new S/MIME certificate and bought one.
But kmail refused all attempts to change the certificate.
Customize K-Mail
Open »Einstellungen« (I guess that’s Settings), Identities, chose an identity, click modify (»Ändern«), Tab Cryptographie: do whatever, nothing will be saved, after restarting kmail it is always as it was before.
kmailrc
In ~/.config/kmailrc isn’t anything related to crypto.
emailidentities 1
I deleted from ~/.config/emailidentities lines like
PGP Encryption Key=123456...
SMIME Signing Key=...
After restarting kmail, these lines come back, but I fail to find the process which writes them back into the file!
emailidentities 2
I terminated kmail (again). Then I opened the file again and replaced the hash of the old private SMIME Signing Key with the new one. I started kmail again. This worked.
Any ideas, why kmail refuses to accept a new certificate and you have to replace it by replacing the hash in emailidentities?