Hello all,
ever since the kmail to kmail2 upgrade years ago I've been having instability problems with kmail, such as 'kmail keeps locking up when checking for new mail'. And the search tool never ever worked.
It happened again yesterday, but rebooting wouldn't solve it.
After playing with akonadictl stop/start and changing the database from internal to my own external, I finally reduced the problem to 'Akonadi control process is not registered at D-Bus'. After doing that also, I restart kmail and... it's a mess.
All folders are messed up (they are in the wrong parent folders), half of them are missing, decade-old messages are marked as unread, etc... Not a complete randomization, but close.
And STILL I get 'Preparing transmission from 'account'' hanging at 0%.

I do have a backup, but it's months old, and I still don't know how to fix it.
I already lost all my work email last year for similar reasons and shifted to Thunderbird, I'd rather avoid losing 25 years of carefully kept messages.
Now what...?

It's not very clear what happened here, but it looks like a severely corrupted configuration. That said, is this mail local? If so, you should find it in the Maildir / mbox files where you originally set it up. (Default for local folders is ~/.local/share/local-mail)

Thanks.
By reverting to the internal mysql server, I got the proper message structure back. Lifesaver.
But how do I get past the "Preparing transmission from 'account'" hang at 0% ? There are plenty of reports on Google but no solution that I could discern.

I fired wireshark and there's no POP transmission whatsoever. I tested my POP account with "telnet mail.wherever.net 110" (hah, good old telnet!) and I get past the USER/PASS/LIST without problem, so it's not a server issue nor a password issue. It's purely a kmail/akonadi issue.

BTW, I'm on kubuntu 12.04 with kmail 4.8.5

Can you try any the following:

- create a new POP account
- create a POP account under a new user account

and see if the issue persists?