Thunderbird persitently defaults to old gmail account upon startup

I have 4 Gmail accounts which I'm phasing out because of Google policies imposition issues.

I've added 4 new different host accounts with my own mail domain as hosting service.

I have all the 4 Gmail accounts set to forward all to the new accounts.
That works.

But the problem is every time I start up Thunderbird it defaults stubbornly to the previous Gmail account which subsequently it obviously cannot log in thus asks for a password.
All this despite I have set the new account as default.

I tried everything, from setting the new account as default account, unchecking google server settings [i.e.check for new messages at start up] on the old gmail accounts.

Since I have much (downloaded) information in sub-folders that I need to access from time to time I have not yet deleted/removed that old google account[s] in TB.

Nothing seems to work, every time I start Thunderbird it immediately goes to that previous old default Gmail account and then prompts me for "mail server password required", which is obviously. All despite that it is no longer the default account and unchecked "check for new messages on startup".

The strange thing is that the other remaining three Gmail accounts which have identical settings do not create a problem.

how can I make this stop for once and for all?

dalchina said:

Please note that you can use the gmail 2FA system once per account to get a new password - an App Password.

Once you have that, you can use Thunderbird or most clients just as you did before.

Sign in with App Passwords - Google Account Help

I've just posted this to make sure you are aware of this.

That is not the issue. I'm not using 2 step verification.
I just want TB stop bugging me every time I start it up.

dalchina said:

And thank you very much for your reply. Good luck.

Sulking?

Tools>Account Settings>highlight account, to be chosen>Account Actions>Set as Default
Maybe that helps

PiKo said:

[FONT="]Tools>Account Settings>highlight account, to be chosen>Account Actions>Set as Default
Maybe that helps
[/FONT]

Tried, nope.

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idgat said:

Delete the Thunderbird prefs.js file in the profile folder, and re-setup your accounts. Assuming you have an SMTP incoming mail server for each, all your mail will be (re)downloaded

Alternatively you could try Tbird add-on Manually Sort Folders which allows you to do just that, as well as set the default opening account and folder.

But in the end, do remember, this is Google mail and the user's preferences are often the last thing they want to allow.

Will try the prefs.js. Have the add-on Manually Sort Folders, no effect.