User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/601.2.7 (KHTML, like Gecko) Version/9.0.1 Safari/601.2.7 Steps to reproduce: Boot the iMac Actual results: Thunderbird terminates immedately after the bootprocess of the iMac has launched it. 16.11.15 12:42:10.000 kernel[0]: thunderbird[392] triggered unnest of range 0x7fff91200000->0x7fff91400000 of DYLD shared region in VM map 0x20d3784e8de31b11. While not abnormal for debuggers, this increases system memory footprint until the target exits. 16.11.15 12:42:15.730 thunderbird[392]: WARNING: The Gestalt selector gestaltSystemVersion is returning 10.9.1 instead of 10.11.1. This is not a bug in Gestalt -- it is a documented limitation. Use NSProcessInfo's operatingSystemVersion property to get correct system version number. Call location: 16.11.15 12:42:15.730 thunderbird[392]: 0 CarbonCore 0x00007fff9074179f ___Gestalt_SystemVersion_block_invoke + 113 16.11.15 12:42:15.730 thunderbird[392]: 1 libdispatch.dylib 0x00007fff9c1e13c3 _dispatch_client_callout + 8 16.11.15 12:42:15.730 thunderbird[392]: 2 libdispatch.dylib 0x00007fff9c1e12bb dispatch_once_f + 67 16.11.15 12:42:15.730 thunderbird[392]: 3 CarbonCore 0x00007fff906ce09c _Gestalt_SystemVersion + 987 16.11.15 12:42:15.730 thunderbird[392]: 4 CarbonCore 0x00007fff906cd8b0 Gestalt + 139 16.11.15 12:42:15.730 thunderbird[392]: 5 XUL 0x0000000104fcfc51 vpx_reset_mmx_state + 535665 16.11.15 12:42:20.782 com.apple.xpc.launchd[1]: (com.apple.xpc.launchd.oneshot.0x10000002.thunderbird[392]) Service exited due to signal: Terminated: 15

Fritz, do you still see this issue? How about if you have started Thunderbird in safe mode? https://support.mozilla.org/en-US/kb/safe-mode

Hello Wayne, Thank you for your help. I've tried without an addons. Same result. Regards, Fritz

can you assist fritz is getting more information about this crash?

Sorry I'm using Thunderbird only on Windows now.

I'm unable to reproduce this issue on my Mac running OS X 10.10.5

Does https://discussions.apple.com/message/29160102#29160102 help?

Hello Wayne, I've tried this. As far as I can see, no unexpected results. What should I do with them? Regards, Fritz

I'm unsure. But the procedure did help the last two people in the thread, starting at https://discussions.apple.com/message/29160102#29160102

I couldnt find any help there. But I have to clarify: The error only occurs when Thunderbird ist started after a new login when on the previous shutdown the checkbox «reopen windows when logging back in» is checked. When I start T'Bird by hand everything seems to be ok. Fritz

I've found the error. Something had happened with the MacOS. I've reinstalled the OS 10.11.3 and after that, the error didn't occur anymore. Thank you all. Fritz