Gene Heskett composed on 2021-11-29 14:11 (UTC-0500):
Some of kde did install but the new kmail 5something doesn't see 7 gigs of old mail, nor will it create ANYTHING not even a new folder.
Did you check to see if KMail5 has an option to /import/ mail from a different app? I'm sure it must have ceased to automatically import from KMail3 many years ago, and has never had same for TDE's KMail.