You can change your email and password in the account manager. If you use TurboTax Online, open a return and select Account Manager from the bottom of the left side menu to get there.
Or you can use this link: https://accounts.intuit.com/app/sign-in?&redirect_uri=https%3A%2F%2Faccounts.intuit.com%2Fapp%2Facco...
