So, some days ago I noticed that Gentoo has got new ebuilds for kdepim 4.6.0. I knew that a new kdepim release had been a long time in the making, and my old kmail from the 4.4.x release was starting to develop some problems with kwallet integration, so I decided to upgrade. I have two KDE/Kmail installations on my computers, one on my notebook, one on my desktop computer, both on Gentoo. On my notebook, I've configured several disconnected IMAP accounts, while on my desktop machine I've got several normal IMAP accounts plus some old POP3 accounts configured.

After upgrading the software on my notebook and restarting, there popped up a "resource migration" window, telling me my email folders needed to be migrated to the new akonadi framework. This took extremely long, much longer than I thought it reasonably should. I didn't time it, but it was several hours. This is not such a big deal if it only needs to be done once, but during the migration, it repeatedly asked me for my kwallet password and for the different passwords for my different IMAP accounts. I've got a few problems with that:

• Why did it ever need my IMAP passwords in the first place, if all it was doing was migrating the local caches and email folders?
• It asked me for my kwallet password more often than I even have accounts configured
• Even after I gave it the kwallet password, akonadi still prompted me for the cleartext passwords of my different accounts. That kinda defeats the purpose behind the whole wallet thing.
• It asked me for those passwords at random intervals distributed over the entire migration process, effectively forcing me to keep sitting there, waiting for the next password prompt. Had I done the sensible thing, that is, lock the screen, walk away and do something else in the meantime, it would have just stuck at the next prompt until I had got back.

The real problems only started after the migration finished:
The first thing I noticed - besides everything being terribly slow - was that a lot of my emails were missing. The top INBOX folders of my different accounts still had their mail, but I'm keeping the vast majority of my mails in various subfolders, and those were completely empty. All of them.
After a bit of a shock moment, I picked up some other IMAP clients (Thunderbird and RoundCube) to have another look at my IMAP-folders, and it turns out the mails were at least still there on the server. At that point I started looking for some option in KMail that would let me manually resync the folders, i.e. some button that would let me tell KMail "Look, your local cache of this folder is obviously broken, just throw it away and redownload everything", but I didn't find such a thing.

So what I did was delete this account and then re-add it with the proper values, thus forcing kmail to redownload everything after all.

That worked, but there were still some weird effects afterwards. Most importantly, some emails showed up in the wrong subfolders. Again, I checked with some other IMAP clients to see that the problems is not in the IMAP-folder itself, but rather only shows up in this particular kmail instance.

This is kind of a big issue for me. I've got a number of email folders that contain high-traffic mailing-lists that I don't always even read, and other folders that contain really important mails. If an email gets misfiled from one of the latter folders to one of the former ones without me noticing it, the effect is pretty much the same to me as if the mail had simply been lost.

Another weird effect is that, around the time I upgraded, in some of my IMAP-folders, mails with corrupted headers started turning up. I haven't much investigated that yet, though, and I don't know if KMail is at fault here.

For another thing, opening a folder (clicking on it in the folder view) has become much slower now. Opening a big folder (20000+ messages) for the first time after startup takes more than a minute. It gets faster after the first time, but it's still noticeably slower than KMail from kdepim-4.4.10 used to be, and several orders of magnitude slower than Thunderbird, and the speedup only holds until the next reboot. Also, KMail and associated processes (akonadi-* and mysqld) now consume about 25% of the 2 Gigabytes of RAM in my laptop. (Measured with top and added up in my head, probably not an accurate figure at all, but it's still consuming obscene amounts of RAM.)

That was the story on my laptop.
On my desktop computer, I didn't even get that far: Whenever I try to open KMail here, I get an error message with the following text:

"KMail encountered a fatal error and will terminate now.
The error was:
You do not have read/write permission to your inbox folder."

and then KMail terminates. I have no idea why I wouldn't have read/write permissions to my inbox folder or what I could do about that...
In contrast to my notebook, I actually did have some local folders with real emails on my desktop

So far, this upgrade has left me with one barely usable and one unusable installation of KMail and the nagging suspicion that it's just no longer a good idea to trust KMail with my emails. Older versions would at least keep my mails in a simple and standard maildir format, that I could still access somehow even if everything else were to break down somehow.

Agreed! This will sound like a flame, but the dev's in the kdepim, kontact/kmail & akonadi don't know #@$% about giving the userbase what they need. errors like this are inexcusable! This is one product that should be user-tested before released. The dev's keep playing with shiny new concepts but don't have a clue how to put together a workable PIM. If thet were employed to put this together they would have been not only fired but thrown out on their collective asses years ago. It's been 4 years and the kde team can't put out a reliable email program? This team is a joke. I've been an ardent kde fan for years. Check my other emails... But this is inexcusable. Somebody who has some leadership ability needs to step in and stop this madness.

For pete's sake... put out a usable application or go back to the last fully functional implementaion until such time as you developers get it together and release a quality product... it's been 4 years already. How much time do they need? Ridiculous.

What's even more ridiculous though is that this type of rant multiplied by a thousand users won't even be picked up on the radar of the kdepim design team. They don't care. They'll assume it's just a rant and go back to talking about how to make akonadi work with some obscure appliance which nobody cares about. yada, yada...yada...

guido wrote:After upgrading the software on my notebook and restarting, there popped up a "resource migration" window, telling me my email folders needed to be migrated to the new akonadi framework. This took extremely long, much longer than I thought it reasonably should. I didn't time it, but it was several hours.

This is weird. Import of cached messages has been disabled before the release because it took too long.
Can you check the kmail-migratorrc in your KDE config directory for a section called [Disconnected IMAP] and post the values?

guido wrote:Why did it ever need my IMAP passwords in the first place, if all it was doing was migrating the local caches and email folders?

Well, some users might want to use the IMAP accounts actively as well, not just the previously downloaded data.

guido wrote:[*] It asked me for my kwallet password more often than I even have accounts configured

Definitely not by design, it should only ask for the KWallet password once.
It would only ask for individual account passwords if retrieving from KWallet had failed.

I wonder if this could be related to the kwallet problems you've mentioned.

guido wrote:[*] It asked me for those passwords at random intervals distributed over the entire migration process, effectively forcing me to keep sitting there, waiting for the next password prompt.

It did that whenever setting up the next account. Since this should not have been necessary if KWallet worked properly this is a follow-up problem.

guido wrote:The real problems only started after the migration finished:
The first thing I noticed - besides everything being terribly slow - was that a lot of my emails were missing. The top INBOX folders of my different accounts still had their mail, but I'm keeping the vast majority of my mails in various subfolders, and those were completely empty.

Under normal circumstances the migrator now only imports the folder structure (to adapt filters and other config) which result in KMail retrieving the folder's contents from the server again.
Looks like it failed to do that.

In your case this is even more weird, since the long migration duration you described hints at messages having been imported.

guido wrote:At that point I started looking for some option in KMail that would let me manually resync the folders, i.e. some button that would let me tell KMail "Look, your local cache of this folder is obviously broken, just throw it away and redownload everything", but I didn't find such a thing.

F5, most likely also as an option in the context menu. (In older versions this was called "check for new emails in this folder"

Cheers,
_