Hi, I am using KMail 5.7.3 in ArchLinux. Since recently (not sure about the version number), I have some delay when sending emails. I tried enabling logs with kdebugsettings export KSMTP_SESSION_LOG=/tmp/smtp.log akonadictl restart Most of the time, the first send attempt fails: journalctl: akonadi_maildispatcher_agent[21670]: org.kde.pim.mailtransport.smtpplugin: Login started akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: TLS negotiation done. akonadi_maildispatcher_agent[21670]: qt.network.ssl: QSslSocket::startClientEncryption: cannot start handshake on non-plain connection akonadi_maildispatcher_agent[21670]: qt.network.ssl: QSslSocket::startClientEncryption: cannot start handshake on non-plain connection akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: Socket disconnected akonadi_maildispatcher_agent[21670]: org.kde.pim.mailtransport.smtpplugin: Removing session KSmtp::Session(0x55e5c5d67ca0) from the pool akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: Socket disconnected Session log: C: EHLO xps.localnet S: 220 smtp.fastmail.com ESMTP ready S: 220 smtp.fastmail.com ESMTP ready Notification: E-Mail Sending Failed Failed to transport messaged. Connection to server lost. Then there is an automatic second attempt which works: journalctl: akonadi_maildispatcher_agent[21670]: org.kde.pim.mailtransport.smtpplugin: Login started akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: TLS negotiation done. akonadi_maildispatcher_agent[21670]: qt.network.ssl: QSslSocket::startClientEncryption: cannot start handshake on non-plain connection akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: Trying authmod "PLAIN" akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: SASL_INTERACT Id 16385 akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: SASL_INTERACT Id 16386 akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: SASL_CB_[USER|AUTHNAME]: ' "john@doe.net" ' akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: SASL_INTERACT Id 16388 akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: SASL_CB_PASS: [hidden] akonadi_maildispatcher_agent[21670]: org.kde.pim.ksmtp: Trying authmod "PLAIN" akonadi_maildispatcher_agent[21670]: org.kde.pim.mailtransport.smtpplugin: Send started Session log: C: EHLO xps.localnet S: 220 smtp.fastmail.com ESMTP ready S: 250-smtp.fastmail.com S: 250-PIPELINING ...
There is a workaround: use STARTTLS.
Thank you for reporting this issue in KDE software. As it has been a while since this issue was reported, can we please ask you to see if you can reproduce the issue with a recent software version? If you can reproduce the issue, please change the status to "REPORTED" when replying. Thank you!
I use STARTTLS, so cannot say if the bug is still there without it. As nobody tried to reproduce after 4 years, closing it.