https://support.mozilla.org/en-US/kb/password-manager-remember-delete-change-tb

Thanks Matt Unfortunately the password was deleted from "preferences" so is no longer available in the profile. When I moved from GoDaddy to Green Geeks, I also lost the opportunity to recover the password from GoDaddy. I wonder if I can set up a new thunderbird account with same email although lose previous data

re : I moved to a new host provider and forgot to note my password.

You can only create, modify etc a password via the webmail account using a browser. If you have forgotten the password, there should be a 'Forgotten Password' link when you attempt to logon. Use that link to reset the password.

Then in Thunderbird

If you can - copy any emails from old account into Local Folders account.

You do not need to create another account - just change the server settings. Make sure you have all the correct server settings. Restart Thunderbird and it will auto try to connect to new server and prompt for password. Enter the correct password and select the 'Remember Password' option before clicking on OK.

If you have moved all the emails from the old GoDaddy account to the new Green Geeks server then it will auto pick up all those emails.

Thanks for your help!