Works with Apple Mail under macOS 10.12.4. It’s easiest if you update to SpamSieve 2.9.28 before updating to 10.12.4. In any case, if you don’t see the SpamSieve commands in Apple Mail’s Message menu, be sure to choose Install Apple Mail Plug-In from the SpamSieve menu. Otherwise, with the SpamSieve plug-in not installed, Mail will move good messages to the spam mailbox without consulting SpamSieve.
Made various changes to improve SpamSieve’s filtering accuracy.
The Save Diagnostic Report… command in the Help menu now works with all versions of macOS that SpamSieve supports.