@ CuteCute
Due to privacy and security reasons, I will not be able to delete any e-mails from your old friend’s account.
However, if you would like to stop receiving e-mails from that specific sender, then I suggest that add his e-mail address to the Blocked Senders list.
When an e-mail address has been included in an account’s Blocked Senders list all e-mails from that specific sender will be blocked.
To learn how to add an e-mail address to the Blocked Senders list, please take a look at the Solution Article “How to filter incoming messages and block or allow from specific sender or domain”.
http://windowslivehelp.com/solutions/settings/archive/2009/03/03/how-to-filter-incoming-messages-and-block-or-allow-from-specific-sender-or-domain.aspx
Moving on, if your old friend has a Windows Live Hotmail e-mail address and would like to report him for harassment, then I recommend that you inform Windows Live Customer Support. Windows Live Customer Support is the best team to address Windows Live Hotmail abuse issues. You can reach them by sending an e-mail to abuse@hotmail.com.