How to Setup Whitelist / Blacklist to block SPAM for VPS running Plesk
This knowledge article will show you how to use whitelist and blacklist to block SPAM :
1. Login to your Plesk Control Panel
2. After logging in, click on "Tools and Settings" on the left navigation bar.
3. Next, click on the Mail Server Settings under the Mail subheading.
4. Next, click on the "Black List" tab.
5. Next click on the "Add Domain" button.
6. Finally, enter the domain name you want to be blocked
7. To save your changes, click on the "OK" button