Wen I use the Kmail import wizard I get all the mailboxes imported but the actual message itself is blank. I see the number of messages, the title, but no message is loaded, going back to The Bat! all the messages are there.
I’ve tried a couple of times, it seems a simple process using the Kmail import wizard, not sure how I can be getting it wrong.
I use the second method, and did shutdown Kmail before importing. The documentation is clear and easy to follow and didn’t see any errors when importing.
I’ve since found that if I double click in the file browser (Dolphin) on a mailbox inbox.mbox then Kmail opens a window and the message is displayed in full, and I have the option to view next and previous messages and they all get displayed in full.
So I can conclude they’ve been imported in full, but I just can’t read the messages in the main Kmail. I must have a setting wrong somewhere
Edit
Attached screenshot, on the left is a message opened in Kmail, on the right the same message opened by double clickking on the inbox.mbox