Maybe you've been hijacked...run your anti virus and spyware removers....while you're letting that run...go to a place with public access to computers and the "internets" to see if you can access them there...
Had the same problem awhile ago ... couldn't open messages, sent messages ... kicked it off cpu, downloaded it again (restart) and same problem again ... Until now i still don't have it (yahoo I mean) ...
They recently switched their look and my home page doesn't come up as www.yahoo.com, but rather as http://m.www.yahoo.com/. Try that. It might work. :dunno:
i've had problems with yahoo mail for a few months now. i occasionally get a message saying there was a problem and it couldn't access my inbox. after clicking "try again" over and over it usually works.
Dude...it's been "days"....it's far more likely to be something with your computer...all computers go to the same internet and it's not likely your ISP is going to have a yahoo specific problem.
Something in your cookies or registry or otherwise is likely the culprit.
Clean all of that up using your virus protection and internet options to clear your cookies...and see what happens.
If it's just your email and it's not recognizing your p/w...it may have been hacked or hijacked by some turd looking to spam on "your behalf" but without your consent (if you know what I mean).