OK, here is my solution to this problem. I updated to evolution 3.16.0 from ppa:fta/gnome3 and it is working right now. and even more, with this version I have server push notification so it is much better user experience!
-- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to evolution in Ubuntu. https://bugs.launchpad.net/bugs/1318971 Title: evolution can not send mail after being open a couple of minutes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/1318971/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs