- 1). Click the "Mail" icon on your dock, or open the "Applications" folder in Finder and double-click the "Mail" icon to run the application.
- 2). Click "Mail" at the top of the screen and select "Preferences" from the drop-down menu.
- 3). Click the "Junk Mail" button and check the box next to "Enable Junk Mail Filtering." Select "Perform Custom Actions" and click the "Advanced" button.
- 4). Click the drop-down list under the "Perform the Following Actions" and select "Delete Message." Click "OK" to save the changes and exit the window.
- 5). Click the "Rules" button and click the "Add Rule" button. Click the "Any Recipient" menu and select "From." In the blank field to the far right, type in the email address you wish to block.
- 6). Click the "Move Message" menu and select "Delete Message." Click "OK" to save the rules.
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