All Thunderbird does is remember and use the last valid password. If password for account has changed, thunderbird cannot assist. If you wish to view the saved password, click to settings>privacy&security and click savedpasswords and then showpasswords. you may be asked then to enter your OS's password prior to viewing them. That password will not work, however, if you are receivng message that password is incorrect.

Hi David, Thank you for your assist, I had already found my way to view my saved password but that is not letting me sign in. i changed my password on Microsoft Outlook the host of my password and it changed the password in Thunderbird but still no access. I am at a loss, originally I found my password but it stopped letting me sign in then I changed it at Microsoft (Hotmail) and it still will no let me sign in and the issue is all my folders are in Thunderbird and I don't want to lose them if I go back to Outlook unless you know how to import the folders... Thanks Derek