How do I change how often yahoo checks for mail?

How do you get Yahoo Mail PLUS to automatically check external POP emails when it checks for Yahoo mail?

• Have Yahoo Mail PLUS. Have external POP accounts that I receive and manage via Yahoo Mail. Problem is that Yahoo mail does not automatically check for new mail in the external accounts, but I need it to do that. How can I get it to do that? Thank you.

• Answer:

  Yahoo! Mail checks your external (POP) mail accounts for new messages only when you request it. To check your external mail account, click and hold down the "Check Mail" button. In the pull-down menu, select either "Check All Accounts" or the single account you want. Messages from the selected account will then be retrieved to your Yahoo! Mail account. You can also use Yahoo! Mail's keyboard shortcut—"M", to check all your accounts. Other options click this link below Why doesn't it work when I check external mail? http://help.yahoo.com/l/us/yahoo/mail/yahoomail/manage/manage-54.html;_ylt=ArrHMHnh2vzA7AyvRdt6J8RkYCN4