Still getting spam email through Yahoo Spam Guard? Do you have an annoying friend who just won't leave you alone? Stop them from reaching your inbox, and automatically delete their messages by adding their email address or entire domain name (such as spammer.com) to the block address list in your Yahoo Mail account settings.
With blocked address list, Yahoo allows you to add up to 500 addresses and domains. Best of all, when a message is blocked, the email does not bounce back to the sender and they will never know what happen.
To set up a block address list, logon to your Yahoo Mail account and click on the Options link under the Search button. Then select Mail Options.
Next, select Spam in the left panel…
and start adding email addresses or domains to the Blocked Email Addresses list by typing in the field and clicking on Add.
When you are finished, don't forget to save your changes by clicking on the Save Changes button at the top of the main window (above the word Spam).
Later you can always come back and remove any email address or domain from the list by highlighting an entry and clicking on Remove (and saving your changes).