If you attempt to log in your account met with the Invalid ID or invalid Password error message. This means you’re Id and password combination doesn’t match in yahoo account record.
Focus on caps lock and number lock to enter user id and password. Case sensitive password entered correctly
Keep a valid Email id and Phone Number on your account. In case lost your username and password, use your secondary email address that is used for account recovery. In Yahoo account can we add 10 email address for recovery.
Edit Recovery info on Web to add an email address
1 Open Web Browser
2 Login your Yahoo Account and click on Account info
3 Go to Yahoo Account security page
4 Click on Add Recovery email address after that comes a pop up of Add Recovery email address
5 Enter Email address and click on send verification email button
This email differs from your account mail id
6 Your Email address is updated on the Recovery mail address
7 An alternate email address added in your account mail come from yahoo account for update a new Mail address.
If you are unable to sign in your yahoo account, use your alternate or secondary email address for access your account.