User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; it-IT; rv:1.8.0.4) Gecko/20060508 Firefox/1.5.0.4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; it-IT; rv:1.8.0.4) Gecko/20060508 Firefox/1.5.0.4 I found that if you launch Thunderbird doubleclicking fastly several times on the Thunderbird icon, you'll get several window open. This doesn't happen if you click on the icon after Thunderbird is fully launched: in this case it's bring up the existing window. This problems seems to affect just the Windows systems (verified on XP an ME), it's not present on Linux. I couldn't test it on Mac OSX because I've not it... Reproducible: Always Steps to Reproduce: 1. launch Thunderbird on Windows doubleclicking fastly on its icon several times Actual Results: you'll get several windows opened, one for each doubleclick Expected Results: you should have just one window opened, as happened on Linux

The same on TB alpha2 (20060823)

If thunderbird is started from Windows quick launch tray using double click then two instances of it will show. A lot of people use double click in this tray (they will never learn, they just everywhere use double click) and they have often two Thunderbirds opened. I think this is dangerous - folder files could be corrupted this way and data lost.

think i've seen this also.

pretty sure comment 3 would have been using trunk. confirming, moving to toolkit+startup.

intendentedelleacque, Tomasz, do you have any additional information? I have not seen this for a couple years. however, if I remember correctly I have seen two Thunderbird processes running such that Thunderbird A not fully shut down and (second) Thunderbird B allowed to open.

I've just reproduced this on Thunderbird 3.1.7 on Windows XP. I think it is easier to reproduce on slower computers or just after reboot. Steps to reproduce: 1. Install Thunderbird, create profile, close Thunderbird. 2. Add Thunderbird to quick launch tray. 3. Click Thunderbird icon in quick launch tray as fast as you can 10 times. 4. After a while you have 10 main windows. This is better now, as there's just one process for all windows.

easily reproduced, exactly as you say Tomasz (and per comment 2). Thanks for retesting. > I think it is easier to reproduce on slower computers or just after reboot. I would think so. I wonder, if perhaps it's still possible to get multiple processes. (a test for a rainy day)

First of all, this is Toolkit code and not specific to Thunderbird. If you double-click on Firefox and SeaMonkey multiple times during startup of the primary instance, you are getting multiple windows as well (most likely spawned by the "remote" mechanism, thus no multiple processes - which indeed would be a bug). The difference is that Firefox and SeaMonkey just open new browser windows when starting while the process is already running, whereas Thunderbird - once it is running - just focuses the main 3-pane window. Thus, there is some special handling involved where Thunderbird catches the remote open request and turns it into a focus, which is apparently established only after startup is completed to a certain point, and hence the default open just happens when requesting an open "too early" before that kicks in. My guess...

I've double-clicked three times on a slow machine after reboot and saw three Thunderbird processes in the Windows Task Manager. Only one of those actually proceeded to a full window. The second one opened another window and exited. The third one exited without opening a window, thus I got two windows in total with just a single process remaining. Assuming that process #2 was still handled by the default Toolkit behavior whereas #3 already met the "don't open me twice" Thunderbird variant, this would confirm the theory described in comment #8.

I usually open thunderbird by clicking on the icon. Since version 17.0 has been updated two different processes open simultanously. I don't know how to find a solution. Could you please help me on this matter? I am not an expert user. Thanks