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Thunderbird crashes on startup with ErrorLoadingBuiltinSheet. bug 1194856

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  • Last reply by Wayne Mery

Bugefun
Bugefun
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Thunderbird 45.2.0 on Windows 10. We upgraded to windows 10 a few weeks ago, but it was still working fine until today.

Every time I run it, it immediately crashes. Even when I run it with thunderbird.exe -safe-mode it still immediately crashes. It just immediately says "We're Sorry" and has the crash reporter. Here is one of the crash reports in normal mode https://crash-stats.mozilla.com/report/index/4148d2cd-b017-44e6-be1d-cf9ff2160721 here is one in safe mode https://crash-stats.mozilla.com/report/index/84e997dd-7a45-4a82-a9c8-201902160721

It looks like it is this bug https://bugzilla.mozilla.org/show_bug.cgi?id=1194856

I uninstalled Thunderbird, and reinstalled it, and the problem is still there.

I backed up my stuff with mozbackup, then uninstalled Thunderbird, then deleted AppData\Roaming\Thunderbird and AppData\Local\Thunderbird . Then reinstalled Thunderbird and it worked (without any emails). Then I exited Thunderbird and restored the emails with mozbackup, and it went back to not working again.

Thunderbird 45.2.0 on Windows 10. We upgraded to windows 10 a few weeks ago, but it was still working fine until today. Every time I run it, it immediately crashes. Even when I run it with thunderbird.exe -safe-mode it still immediately crashes. It just immediately says "We're Sorry" and has the crash reporter. Here is one of the crash reports in normal mode https://crash-stats.mozilla.com/report/index/4148d2cd-b017-44e6-be1d-cf9ff2160721 here is one in safe mode https://crash-stats.mozilla.com/report/index/84e997dd-7a45-4a82-a9c8-201902160721 It looks like it is this bug https://bugzilla.mozilla.org/show_bug.cgi?id=1194856 I uninstalled Thunderbird, and reinstalled it, and the problem is still there. I backed up my stuff with mozbackup, then uninstalled Thunderbird, then deleted AppData\Roaming\Thunderbird and AppData\Local\Thunderbird . Then reinstalled Thunderbird and it worked (without any emails). Then I exited Thunderbird and restored the emails with mozbackup, and it went back to not working again.

Modified by Wayne Mery

All Replies (1)

Wayne Mery
Wayne Mery
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Good research.

No fix in sight in the bug report, and no workaround listed. https://support.mozilla.org/en-US/questions/1127088 solved by reinstalling and restoring a backup, but apparently that didn't help you.

I don't have a workaround to offer. But I'm not certain the bug report is a good match for Thunderbird users. I suggest you try in the web interface for your mail system deleting/moving messages with date+time in the vicinity of when you started crashing. Is that possible?