Well, that varies from my experience.

But no matter. Go to Tools|Options|Security|Passwords→Saved Passwords and delete the incorrect one. Then Thunderbird should ask for the missing password next time you need it.

I am using Apple Computer running OS X 10.10.3 I have found some guide to in the Manual Account Configuration to set up the smtp, but the example is not the same as my existing indication from my Apple Computer, the example showing that we can choose User name and Password in smtp set up, but in my Apple Computer, I can only select username, can't find any method to fill in the password. I am using a web hosting service from Hosting Supplier, the Username and password of incoming and outgoing is not the same, so that I need to fill in 2 username and password during set up, one is for incoming, the other is for smtp outgoing, in the current situation, in smtp set up, it allow to fill in username, but not allow (or I can't find the way to fill in the password for smtp) enclosed please find to screen capture, one is the example from Mozilla Support, the other is my current situation. Many thanks

Perhaps take notice of the good information your getting here and stop posting about irrelevancies your finding on the web and you will move forward with the issue.