Hello house, some time ago i have being having this problem of signing in to yahoo mail and yahoo messenger is not only that,
is even too very slow. until i found the little secret that firewall can cause.
what i did is that i off my firewall and that solve my problem of signing in both yahoo mail and messenger it even increase the speed of my browsing.   

How to off your firewall.
(1) click on your start icon
(2)click on Control panel
(3)Look for window firewall and off it.
that is all after that Ur system browsing speed will be increase

just try it and post Ur experience

you are playing with fire

do yyou actually know the function of the firewall

dumbass

A firewall is software or hardware that checks information coming from the Internet or a network, and then either blocks it or allows it to pass through to your computer, depending on your firewall settings.

A firewall can help prevent hackers or malicious software (such as worms) from gaining access to your computer through a network or the Internet. A firewall can also help stop your computer from sending malicious software to other computers.

By default, most programs are blocked by Windows Firewall to help make your computer more secure. To work properly, some programs might require you to allow them to communicate through the firewall. do that instead of turning the whole firewall off