To go to the classic mail Log in, On the top middle screen there should be a mail Classic botton. Click on it and something appears that says your about to leave yahoo mail , but then click switch back to yahoo mail classic. Then you should be switched back to your old mail.To switch back to the new Yahoo! Mail, just click “Options” in the upper-right corner of your Yahoo! Mail page. On the Options page that opens, the message ” The new Yahoo! Mail has arrived! Try it now!” appears in the upper-right corner, just below the “Options” link. Click “Try it Now!” to get back to the new Yahoo! Mail.