I have several different accounts on my mac mail account. The top one is my main account and that one is running properly and goes to the POP account to get the mail without fail. I have three other accounts for other family members and they all will show a triangle next to the account name and for some reason not be able to check the account. Mail says that the "Mail server denied access to the account because an administrator or other mail client was using it when Mail tried to log in. Please try again later" I would think that Mail would try to log on one account at a time but maybe I have something set wrong. Is there some sort of setting I need to adjust????