Some people are amazingly persistent. It's no use talking to them. Maybe ignoring them does not help (them) either, but at least the annoyance stops.
More Email Quick Tips
Block a Sender in Mac OS X Mail
To delete all mail from a certain sender automatically in Mac OS X Mail, set up a new message rule:
- Select Mail | Preferences... from the menu in Mac OS X Mail.
- Go to the Rules tab.
- Click Add Rule.
- Make the criterion read From Contains.
- Insert the email address of the person you want to block.
- From the actions, select Delete message.
- Assign a Description to the new rule.
- Close the dialog with OK.
