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How to stop Thunderbird opening a second time?

  • 2 replies
  • 1 has this problem
  • 2 views
  • Last reply by Matt

Hershmab
Hershmab
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I have two PCs running TB under different Windows versions. Under Windows 7, if I try to open TB while there is already an open window, TB simply reactivates the first window.

Under Windows 8, when I think I have closed TB, the TB process apparently continues in the background. If I then go to open it, there is an error message saying that it cannot reopen. The only way I can then activate it (without rebooting) is to use the Windows Task Manager to close the background process.

There used to be an option to set TB to behave as it does on my Windows 7 PC which I must have retained when shifting my profile to different machines. The Windows 8 PC was set up without reference to previous profiles and so seems to have lost this option as I can no longer find it on either PC.

How can I activate the relevant option on the Windows 8 machine?

I have two PCs running TB under different Windows versions. Under Windows 7, if I try to open TB while there is already an open window, TB simply reactivates the first window. Under Windows 8, when I think I have closed TB, the TB process apparently continues in the background. If I then go to open it, there is an error message saying that it cannot reopen. The only way I can then activate it (without rebooting) is to use the Windows Task Manager to close the background process. There used to be an option to set TB to behave as it does on my Windows 7 PC which I must have retained when shifting my profile to different machines. The Windows 8 PC was set up without reference to previous profiles and so seems to have lost this option as I can no longer find it on either PC. How can I activate the relevant option on the Windows 8 machine?

All Replies (2)

Hershmab
Hershmab Question owner
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Or have I misinterpreted the Windows 8 behaviour? Everything I have seen on this topic (better described as multiple instances) suggests that reactivating the already-open instance is the default!

This raises the secondary question: what is it that closes the TB task without closing the background process? I come across this problem some times in FF also.

Matt
Matt
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  • Top 10 Contributor
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The usual cause of that is anti virus programs causing the program to hang on exit. Add-ons and other security programs are also suspect of course.

To diagnos your issue

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.