Click on the FTP Manager link
in the Site Management area.
Click on the
delete button 
next to the account
you wish to delete.
Deleting an FTP account is as simple as creating as creating the account. Deleting the account does not delete the folder or its contents, but it does prevent anyone from accessing that folder through FTP.
To delete an FTP account:
Click on the FTP Manager link
in the Site Management area.
Click on the
delete button next to the account
you wish to delete.