How did you set up the two accounts. Have you tried to download mail, manually,? i.e. hitting Get Msgs button?
I have, just, checked my Mail, and the two accounts are only some of the many which I have. They are set up as imap accounts, and Yahoo has rarely failed to work. When it failed I got a server error. But this morning it worked. As usual, one good mail, three directly to Trash, as directed for Spam, and four stubborn ones in the Bulk mail folder. I get very little mail from AOL.
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A minority may be right, and a majority is always wrong
~ Henrik Ibsen
WinXP, SP3, 512 MB, SM2.17.1, FF21, TB17.O.5, IE8.0, Google Chrome 26, Ghostwall , Kingsoft5.6, JRE1.7_21.