Darren wanted to know if there is a way to change the birthday information he supplied at the time of Yahoo account creation. Quick answer - Nope! There is no way you can change your birthday on the Yahoo account and profile.
The birthday along with country of residence and postal code are required to verify your identity when you've forgotten the Yahoo ID or have Yahoo email password issues. Yahoo follows the logic that each of us has only one birthday (even if you've been 'born again') and you had used the same when you created the ID. By the way, supplying false information during account creation is against the terms of service. So what can you do? Can you at least view this birthday information?
Sorry! Yahoo won't even display the date you had supplied as your birthday. The "Account Info" page would have the birthday as "On file". You can't see it and can't edit it!

Firstly, I'm not sure why you would have supplied an incorrect birth date when creating a new Yahoo account. You already know that you can't change or view this information yourself - you need to contact the Yahoo support either via phone or email.
Page contents: Yahoo account access information: Change birthday on Yahoo profile. Edit or view the birthday information.
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