Yahoo Mail does not log in


Jun 15, 2012
Hi guys, I dont know if this is the right place to post this, but I'm very frustrated and unhappy. I can't log in to my yahoo mail (I can't sign in) I am a 100% sure that my yahoo ID and password are correct. Whenever I type them in, I always get "Invalid ID or password.
Please try again using your full Yahoo! ID."

I have tried opening my mail on 4 different browsers(IE, Chrome, Mozilla ans Safari) all to no avail. I found a trick though, I open my mail from yahoo messenger, it redirects me to my browser and i can check my mail, but this is a long process for me.

Please can you tell me how to resolve this problem about not being able to log in form my browser? Thanks in advance.