To diagnose problems with Thunderbird, try the following:

• 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.

Matt

Thank you for your prompt and helpful reply, which appears to have resolved the issue. I have abandoned use of all add-ons.

Kind regards

Hawksignal

Hawksignal said

To Whomever can help: My desktop installation of Thunderbird has, since 17 August, developed multiple flaws, namely: I am not able to view my inbox (or any folder) without opening it in a new tab; I am unable to write new emails; I am unable to isolate unread emails; Thunderbird does not open from the taskbar or desktop but is running according to Task Manager, from where I have to terminate the application in order to launch it again. It responds very slowly; I am unable to access ANY tasks from the Menu. I am running Windows 8.1. I have saved my profile and restored to a new installation of Thunderbird to no avail. Any assistance would be greatly appreciated as T-bid has become unusable in this state. Many thanks HS

Hi, I have all these same problems. I cannot follow the suggestion because most menu options, including those for turning off add-ons or restarting without add-ons, fail to work - a part of the problem set. Can I remove add-ons any other way? I do not know where they are located.

joejacobs,

I recommend following Matt's advice to the letter, and open T-bird under your OS in safe mode (I'm using the lamentable Windows 8.1). I had the same problems: T-bird was unresponsive BEFORE a re-start. I therefore suggest a clean restart and try disabling settings in T-bird thereafter. I've removed all add-ons as default. They are located under the menu button on your right of the screen (an icon of three stacked bars).

Good luck

hi hawks, I am in safe mode currently (with connection) and it makes no difference I am afraid. most menus are present but very few of the commands execute. if it helps in diagnosis, I also find thunderbird continues to run after I close it, on an erratic basis - i.e. frequently but not always. Also, if I click on a folder in the left hand list, although it does not appear in the right hand pane, if I move my cursor over the emails listed on the right they disappear! (because they are no longer selected presumably). Is there any way I can get at the add-ons from outside the programme? tx Joe

@Joe, what you describe here and what you describe in your question https://support.mozilla.org/en-US/questions/1079629 are not entirely the same. I have no intention of working with you here when you have a support topic of your own open. But I suggest you understand some windows repairs as it sounds like you might have more problems than an oddly behaving Thunderbird.

From the Accessories on Start menu, Select the system tools

Use the disk cleanup tools. No better? Run the disk defragmenter. (it will stop and require a reboot to check the disk for errors and may spend an hour or more checking. So be ready for a long wait, like while you sleep.)

locate the desktop shortcut for Thunderbird and edit it to place. -options and -offline after the "target" start Thunderbird.

Dear Matt &| Hawks, thanks for your help. Reading the original posting, I am not sure what you see that is different about my problem. It seems identical, but you must be right because unlike the original poster, I cannot effect your remedy of removing add-ons, because this option is one of those that does not respond. As with the original post, I can only open my inbox by opening it in a new tab and clicking on that pane. Also Thunderbird.exe continues to run after I close it, until I kill it. I cannot seem to uninstall TB, even by hand deletion of files. When I re-install it, it has retained the tabs I had previously opened. I have tried using safe mode etc. and followed suggestions re Disk Tools etc. (I have SSD disk) Can you help? Tx joe

Ok, thanks all. It was not Windows, but it was add-ons. My problem was that I could not alter any add-ons as that functionality was one of those no longer working. Matt mentioned command line options for TB and I found the -safe-mode command line option allowed me to remove add-ons both temporarily and there-after. Everything has returned to normal. I don't know but I suspect the recent update integrating calendar functions with TB may have contributed. Thanks all

Good to know.