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I can only open Thunderbird in Safe Mode or it freezes and flashes?

  • 7 replies
  • 2 have this problem
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  • Last reply by sfhowes

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After Windows 10 performed critical updates, my Thunderbird program no longer launches without freezing and crashing. I can start it in safe mode and it seems to perform as it should. I have removed all add ons and extension and even recommended hidden files that was causing it to open multiple windows, as many as 30 or 40 at a launch. Do not know what to try now, any suggestions? Thanks in advance for any helpful advice.

After Windows 10 performed critical updates, my Thunderbird program no longer launches without freezing and crashing. I can start it in safe mode and it seems to perform as it should. I have removed all add ons and extension and even recommended hidden files that was causing it to open multiple windows, as many as 30 or 40 at a launch. Do not know what to try now, any suggestions? Thanks in advance for any helpful advice.

All Replies (7)

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Let's start with, what addons did you / do you have installed?

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The only addon that was listed was Lightning and I first disabled and then completely removed.

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Safe mode also implies the default layout is applied, hardware acceleration is disabled etc. First, launch in safe mode, check 'Reset toolbars and controls' and click 'Make changes and restart'. If the problem remains, change the hardware acceleration setting in Tools/Options/Advanced/General (if it was on, turn it off). If that doesn't help, open the profile folder (Help/Troubleshooting Information, click Open Folder), close TB and delete directoryTree.json , foldertree.json (used by folder pane) , mailviews.dat (message views) , search.json, session.json (snapshot of the windows layout), and XUL.mfl (cached user data) - reference.

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Tried all suggestions and still if I try to launch it normally, it either freezes up and does not open or opens with multiples windows of between 27 to as many as 40? I think I will have to continue to open in safe mode or do not have a usable email app.

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At this point I'd recommend you create a new profile with Profile Manager (Winkey+R, type thunderbird.exe -p), add an account, and see if your problem remains. If it works OK, you could add your other accounts and transfer your mail and contacts etc. from the old profile.

But if you still have problems, report here for further advice.

Although I doubt a Windows update would cause this problem, the update may have coincided with other 3rd-party updates, such as drivers and security programs. To test this, start Windows in safe mode with networking (Shift+Restart) and see if your existing profile works in TB normal mode.

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I will try to go to profile manager and create a new account, not sure about my computer abilities to do this? Does it hurt to continue running Thunderbird in Safe Mode?

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There's no major loss of functionality by running in safe mode, except you won't be able to use add-ons, including the Lightning calendar. But it is fairly easy to use Profile Manager and switch between profiles until you get things working properly.