What is your anti-virus software?

I'm using Webroot SecureAnywhere. ThunderBird is set to not allow anti-virus to scan incoming messages.

ThunderBird is set to not allow anti-virus to scan incoming messages.

Interesting. How did you do that?

Try to start *Windows* in safe mode with networking enabled.

- Win8 http://windows.microsoft.com/en-US/windows-8/windows-startup-settings-including-safe-mode

- Win7 http://windows.microsoft.com/en-US/windows7/Start-your-computer-in-safe-mode

- XP http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx

Still in Windows safe mode, start Thunderbird in safe mode.

- https://support.mozilla.org/en-US/kb/safe-mode

Does the problem go away?

I wasn't planning on messing around with Safe Mode, because it usually means having to disable something inside the system to get it to work. I'll just deal with it.

Either way, TB has a setting for antivirus clients. I'll try checking that and see if that helps.

re: I wasn't planning on messing around with Safe Mode, because it usually means having to disable something inside the system to get it to work.

It is a debugging feature and it is simple and quick, but it does offer very specific information which can be used to identify issues or rule those issues out.

Test Windows 8.1 http://windows.microsoft.com/en-US/windows-8/windows-startup-settings-including-safe-mode Choose to boot in 'Safe Mode with Networking'. If Thunderbird runs ok, then there is an issue with an external program which is not running in Windows safe mode.

If no there is still a problem

Test Thunderbird Safe mode: In thunderbird: 'Help' > 'Restart with addons disabled' If the problem goes away then the issue is with an addon.

Other reasons for a temp delay in any process could be eg: scheduled background updates or Thunderbird opening / using large mbox files amongst many possibilities. Here is a link which you could use to help identify what is causing or rule out what is not causing, the issue.

• http://kb.mozillazine.org/Performance_-_Thunderbird

Ok, it looks like it's because I'm using IMAP (remote folders). It must it's be a delay opening the trash folder the first time. That and there's a bajillion messages in trash.

Delete everything in trash and you won't have ongoing problems related to that folder. If you are using trash as a "I want to keep this forever in case I want to get it back" folder, not a good idea.

Fastest method is right+click on trash folder, Empty

I'm having the same problem when attempting to delete messages. It only started happening about a week ago.

Wayne Mery said

Delete everything in trash and you won't have ongoing problems related to that folder. If you are using trash as a "I want to keep this forever in case I want to get it back" folder, not a good idea. Fastest method is right+click on trash folder, Empty

Wayne, your answer is useless and based on guessing. It is not related to Antivirus nor the size of Trash folder. It can be empty and the problem will occur on some computers running Windows 8.1 but will not on others.

erlandas said

Wayne, your answer is useless and based on guessing. It is not related to Antivirus nor the size of Trash folder. It can be empty and the problem will occur on some computers running Windows 8.1 but will not on others.

Wayne Mery said

Delete everything in trash and you won't have ongoing problems related to that folder. If you are using trash as a "I want to keep this forever in case I want to get it back" folder, not a good idea. Fastest method is right+click on trash folder, Empty

It might have been more productive for you to point to your posting at https://support.mozilla.org/en-US/questions/1039619 than blast someone else's advice, to someone else's issue.