Bug 817281

Thanks for a bug report. Evolution relies on NetworkManager notifications about network availability for reporting online/offline state, and this is also indicated by the online/offline button at the left-bottom of evolution's window. You can also switch this mode on your own, by File->Work Online/Offline (it shows the opposite state than evolution is in). Evolution cannot be turned online when it's offline by NetworkManager notification. To have this fully working you should have installed also evolution-NetworkManager, but as you suggested in the description that evolution gone offline on network unavailability, then I guess you have it installed. The automatic move from offline to online is done only when evolution was moved to offline due to NetworkManager notification, if it's in offline due to user's will then it stays in offline regardless NetworkManager notifications.

Is it possible you moved to offline by accident before the network outage had been notified to evolution?

It seems to me as the most likely scenario, because the usual steps are:
a) evolution runs in online
b) after some time NetworkManager notifies about network outage
   b1) evolution receives notification and moves itself to offline mode
   b2) there is shown a notification panel about offline state due to network
       unavailability
c) NetworkManager notifies about connection availability
   c1) because of forced offline due to previous NetworkManager notification
       evolution moves to online automatically
   c2) panel from b2) is removed automatically
It worked this way the last week, when I was playing with online/offline notifications.

If you run evolution from a terminal, then you may see some messages from evolution about forced oflfine/online when it receives notifications from NetworkManager.

At this moment, I strangely don't manage to reproduce the error!

I controlled, and I have Network-Manager installed.

I'm absolutely sure not to have put Evolution offline with the network-manager.

It seems however, that
https://bugzilla.gnome.org/show_bug.cgi?id=646801
would have some bearing with this problem.

I will try for some time to start Evolution from the terminal, so in case the problem will represent itself, I may see what is happening.

thank you very much!

(In reply to comment #2)
> It seems however, that
> https://bugzilla.gnome.org/show_bug.cgi?id=646801
> would have some bearing with this problem.

Hmm, I understood your report differently, I thought the button itself is disabled (as it is when evolution is offline), not that clicking Send/Receive button on the toolbar gets stuck in processing, about which is basically the upstream bug.

Yes, you understood it right. the button was DISABLED. 
My technician informed me of that other bug, and he thought it might give an idea, being a bug in some way similar.
If you think the two cases can have nothing to do with one another, than let's forget the 646801. 
I confirm that the button was disabled as when Evolution is offline.

many kind regards

OK, no problem. I think this issue is rather about missing notification about established connection. The 3.6.0 (to be in Fedora 18) will not use NetworkManager directly, but it'll use GLib's network monitor. But that's another half a year far away.

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