Yahoo mail configuration on Windows mail fail to work

I am trying to configure Yahoo on Windows mail. I am using AT&T network. I think there must not be any problem with it. The mails configuration settings are quiet common. But when I try to configure on the default settings I am getting that the mail server does not exist. I need some help here. Does the settings vary as per ISP in the market.

You can contact your ISP for that. I am not sure about that. But there are chances that some settings might differ. I had found on some download a small configuration tool that automatically configures the mail settings.