Verified answer

Something went wrong on YMail and there have been thousands of "error" messages. Right now there are no workarounds. Yahoo knows about the problem and they will fix it.

If it is new version then go back to classic because i was also was suffering from same problem.

To go back to YAHOO! MAIL CLASSIC...

Turn off Javascript - you'll then be asked if you want to return to Mail Classic, click "yes".

If you don't know how to turn off Javascript...

For IE: Open TOOLS > INTERNET OPTIONS >> SECURITY. In security click "CUSTOM LEVEL" -> disable active scripting in the scripting section.

IMPORTANT:Remember to turn JAVASCRIPTING back ON when you are back in Mail Classic because without it some mail functions won't work.

For FIREFOX: Open TOOLS -> OPTIONS -> CONTENT, click on "DISABLE JAVASCRIPT". Now hit F5 to refresh the page while you are in Yahoo! email in order to switch back... In the options, click (PERMANENT) to switch back to YAHOO! Classic. DO NOT click the "ONE TIME ONLY" option.

IMPORTANT: Turn JAVASCRIPT back ON once you have your "CLASSIC" account back.

I can't answer your question, but I nam having exactly the same problem since yesterday.