Hi, I have forgot my new password for my Yahoo id after changing it. I remember the personal details provided at the time of registration, but I don't remember the answer of security question. And also I am not using the alternate email id provided at the time of registration. Can anyone help me in getting my password.

If you can't answer the security then you will need to contact Yahoo and plead your case.
Don't hold your breath as I don't hold out much hope with that.