I want to confirm the error
I have two different users accessing the same mail server via Kmail, one user can recieve mail normaly, the other one gets exactly the same behaviour you discribe.
I already renamed all files obviously related to Kmail and Kontact (kmailrc, apps/kmail/, ...) and recreated my Mail settings from scratch, but it did not help.
Does Kmail (or one of the KIOslaves) have other files which are used to store something in?
I hope someone can help, if you know the answer, please notify me by eMail (I will use thunderbird for now
).