There are two ways to update to the latest version of SpamSieve:
Automatic Updating
Manual Updating
Go to the SpamSieve Web site and click the Download (Free Trial) button.
Quit SpamSieve and your mail program.
Replace the old SpamSieve application file with the new one. That is, if SpamSieve is installed in the Applications folder, drag the new SpamSieve application icon into the Applications folder and click Replace when the Finder asks if you want to overwrite the old version.
Note: If you get an error saying that the file is locked or you do not have sufficient privileges, drag the old SpamSieve to the trash and empty it, and then drag the new one into the Applications folder.
Launch SpamSieve and your mail program.
macOS Updates
It’s best to update SpamSieve before updating macOS. To prevent macOS from updating itself without asking you, go to the App Store section of System Settings and make sure that Install macOS updates is unchecked.
Repeated Update Prompts
If SpamSieve keeps telling you that a new version is available, even after you’ve updated, you may still have the old version somewhere on your Mac. There should only be one copy of SpamSieve installed, and it should be stored directly in your Applications folder. If you see a window saying that you need to update SpamSieve, you can Command-click on the SpamSieve icon in the Dock. This will reveal the location of the SpamSieve.app file in the Finder so that you can see where the old version is and delete it (after quitting SpamSieve).