I’ve done a posting search for this, see no fix to it. And there’s no error log for this when it happens for me. I have “options” set to “send messages immediately”. Has there been a fix for this in the free (or Pro) version of eM Client?
if the message gets stuck in outbox, there must be a reason/error in the Tools>Operations>Error or Log window.
Please check there right after sending the message/try the Send&Receive button to trigger sending the stuck message again and then copy the content of the Log window.
I’ve just discovered why there’s also been 1 ‘unsent’ message in my Sent box . . . it’s not that that it was not sent, it’s that there’s a sent message in the message list that hasn’t been opened/viewed (a la Inbox views). Perhaps this is the appropriate answer for anonymous!