In order to be able to use the 'forgot password?' option with your Ameritech email account, Microsoft requires you to set up a second authentication method (i.e. phone number, alternate email, etc.)
You can add these to your account by following this link: https://account.activedirectory.windowsazure.com/PasswordReset/Register.aspx?regref=ssprsetup. Log in with your Ameritech email and set up other forms of authentication so you don't get locked out of your account!