when i receive my emails there seems to be an email which is in excess of 4mb which never downloads how do i get rid of this email
Hi. Welcome to the forums.
How are you accessing the emails ? Is it via Outlook, Windows Mail or Thunderbird for example ?
If so, then login to webmail via a browser, e.g. http://mail.yahoo.com using your full email address as the Yahoo! ID. You can delete the email in there, or perhaps move it to a different online folder.
Did you go to the webmail link provided by AN?