Yahoo mail /Plus log on, send

Question

I cann not log on to Yahoo by itself as before. My Yahoo mail also is transferred to Outlook through Yahoo Mail Plus.
How can I go directly to see what comes in there --seoararted out? Also Yahoo sending error from Outlook's Outbox has prevented two e-mails from sending from Outlook.

Can you help straighten this out? How do I conatact Yahoo by phone - and is it worth it?