If I enable antispam filter (SpamAssassin or SpamBayes) I recive more than once every incoming e-mail.
It happens with IMAP account on Polish e-mail provider www.onet.pl. It doesn't happen with GMail. It has been observed for "auto checking for new e-mails" functionality.
The problem doesn't exist if antispam filter is disabled.
Steps to Reproduce:
1. set up an mail account on www.onet.pl (free of charge)
2. configure above account with kmail (IMAP way)
3. set up antispam filter
4. send e-mail to yourself
5. check for new e-mails on kmail
Identical messages are proliferating in my kmail mailbox and thus on mail server. They've got the same incoming date and titles.
One message on mail server. One message in my kmail mailbox.
I suspect, it can be encoding that an provider uses, i.e.
Content-Type: text/plain; charset="ISO-8859-1"
Content-Type: text/html; charset=UTF-8
Above are from message source.
Maybe some Kmail routine have problems to compare e-mails on server with e-mails that I already received and sends me something that I already have.
I have a similar problem with a POP3 account - I have SpamAssassin and Bogofilter installed and I also apply filters on the sender's email address to classify my messages into separate folders. About 1 out of every 3 emails from those that are filtered to go into one of the folders (but not the ones staying into the generic inbox) are duplicated. It seems related to Bug 283682 (but I am not sure).
Please let me know what types of log / tests I can provide
Sorry, forgot to specify I am on KDE 4.11.2 on OpenSUSE 12.3
Probably the same problem described in Bug #316419?
For me it seems to be the same problem, yes,
There are quite a few bugs around here complaining about duplicate emails after filtering. I found Bug #316419, Bug #95064, Bug #322126, Bug #322676 and there are probably even more.
Perhaps someone (a kmail developer?!) could check which bugs actually describe the very same problem, choose one of them to work on and mark the others as duplicates.
This is really annoying and I would love to see this fixed – I delete quite a lot of duplicate emails by hand each day.
I still see the problem in kmail-4.12.0.
This is very likely caused by the problem described in Bug #283682
*** This bug has been marked as a duplicate of bug 283682 ***