Not accepting SMTP password

Hi: I have Yahoo Small Business Mail. Small Business Mail allows you to setup sub mail accounts off the main account so you can log in once and have access to all your business accounts. Recently I changed the password for the main Yahoo Small Business mail account. Once I did this, I had to reset the password for IMAP on Thunderbird for all my Sub accounts and the main account. Also, when I first sent an outgoing email via SMTP, I had to once again provide the password. This worked great for all accounts except my default or main account. It just won't accept the new password (or the original password.) I know the password I'm using is correct because it works on all the sub accounts. I also can log directly into Yahoo Small Business Mail with the new password with no problem. Has any one else had this problem? Any ideas? Regards, Tom