Since adding an aol account is pretty much automatic I would start by removing the account from the mail app. Open mail, in the top menu click on Mail>Preferences. Then click the Accounts tab. Click on your AOL account to highlight it. Then on the bottom click the - sign. Then click the + sign and type in your address and password. That's where I would start.
Actually it isn't. I just set up another AOL to try it out. There is a check box under the name and password that says "Automatically set up account." Works like a charm.
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