That bug has been opened on https://launchpad.net/distros/ubuntu/+source/evolution/+bug/43760

"this is just an annoyance, but i think it's worth reporting it nevertheless: warning dialogs (for example: "connection to imap server lost" etc) have the nasty habit of stealing focus, and it's very annoying when you are busy with other tasks such as writing mails, browsing the calendar etc, regards, andre
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iam totally on your side! my workflow is often interrupted with this popups, too

But, warning messages are there to warn you and get noticed. Perhaps its essential for you to notice that you can receive or send emails at the moment. Perhaps not.

A dream of a solution would be:
Making it possible to minimize evolution to a icon in the notification area, or a panel-applet. Then you have the possibility to show notification messages instead of popups. Perhaps mail-notification can do this job, and act more like a remote-control for evolution. On my notebook i often have interruptions and changes in the network-connections and dont use the mail-notification because of this.

Using notification-messages would be better than popup warning dialogs, they dont steal focus. And they stay a while or until you click them as ack. away.

br, Sven
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<essential for you to notice that you can receive or send emails at the moment.
>essential for you to notice that you can not receive or send emails at the moment."