The only way that setting could be related to the problem would be if some other application is trying to use the default mail client for some reason when you log in. You may try setting Apple Mail as the default mail app, just to see if that causes Mail to open instead…

The only way that setting could be related to the problem would be if some other application is trying to use the default mail client for some reason when you log in. You may try setting Apple Mail as the default mail app, just to see if that causes Mail to open instead…

Thanks for getting back to me so quickly, David. I'll give it a try. Any other ideas about what's going on?

re :Thunderbird always asks for my primary password

The wording 'Primary Password' is very specific and only relates to a specific password you set up to stop all other people who have access to your computer and who you allow access to your computer User Account from being able to get access to you saved passwords in Thunderbird. It has nothing to do with mail account passwords.

It is something you set up but do you really need the 'Primary Password' ? Do you allow other people full access to your computer and user account? If no then it's only you being prevented from auto access.

This is where it is set up: In Thunderbird

• Settings > Privacy & Security
• scroll down to 'Passwords section

If the 'Use a Primary Password' checkbox is selected then you set it up.

• If you want to remove it then click on 'Change Primary Password'
• Follow instructions.

More info here:

• https://support.mozilla.org/en-US/kb/protect-your-thunderbird-passwords-primary-password

re : I don't want Thunderbird opening automatically.

Thunderbird only starts up when you start computer and logon to your computer User Account IF Thunderbird has been set up to start up automatically when you logon. This has nothing to do with the Primary PAssword and it's not a Thunderbird setting.

This is simple fix, but this is very specific to a MAC. Maybe you have only just acquired a MAC computer. I don't use a MAC but a goggle search located the following info. I suggest you deselect the 'Open at Login' option. The simplest way to disable an app from launching on startup is from the Dock. Control-click on the app and hover over Options in the menu. Apps that are set to open automatically will have a checkmark next to Open at Login. Click that option to uncheck it and disable it from opening.

Helpful Info link: https://uk.pcmag.com/macos/134423/how-to-stop-mac-apps-from-launching-at-startup

No, setting Thunderbird as your default mail client should not cause Thunderbird to be launched when you start your computer.

You have ruled out my first two guesses: 1) You shut down with the option to re-open windows when logging back in and Thunderbird is still open; 2) Thunderbird is set to open on start-up in System Settings.

I have only one other guess, and it's just a guess. Check the file system for files that cause apps to open automatically. Do you see anything related to Thunderbird in the following locations?

~/Library/LaunchAgents /Library/LaunchAgents /Library/LaunchDaemons

The tilde (~) refers to your user account. The folders without a tilde are at the root of your file system. Please tell me if this is not enough information for you.