Version 2.9.39 of SpamSieve is now available.

Save time by adding powerful spam filtering to the e-mail client on your Mac. SpamSieve gives you back your inbox, using Bayesian spam filtering to provide amazing accuracy that’s constantly improving. SpamSieve learns and adapts to your mail, so it’s able to block nearly all the junk—without putting good messages in the spam mailbox. It’s quick and easy to control SpamSieve from within Apple Mail, Airmail, Entourage, MailMate, Mailsmith, Outlook, Postbox 5, PowerMail, and more.

SpamSieve running on your Mac can keep the spam off your iPhone/iPad, and you can even train SpamSieve from your iOS device.

SpamSieve protects your privacy. It does not need access to your mail account login and does not transmit your mail data anywhere. All the processing is done on your Mac.

This is a free update that includes the following changes:

• Made various changes to improve SpamSieve’s filtering accuracy.
• When you select spam messages in Apple Mail, the message list text is more readable through a variety of highlight colors.
• Improved the following sections of the manual:
  • How can I copy my training data to another machine?
  • If the Apple Mail Plug-In Doesn’t Appear in the List or Doesn’t Stay Enabled
  • Setting Up Airmail
  • Setting Up an Apple Mail Drone
  • Turning Off the FastMail Spam Filter
  • Why are messages marked as spam in Apple Mail but not moved?
• Added the Processing Messages Before SpamSieve and Setting Up Airmail 1–3 sections of the manual.
• Worked around a change in the forthcoming macOS 10.15.4 that could prevent Mail from loading SpamSieve’s plug-in if you had relocated your home folder to another volume. If Mail reports an error loading the plug-in, choose Install Apple Mail Plug-In from the SpamSieve menu to update it.
• Worked around an Apple Mail bug that could, in rare cases on macOS 10.15, cause spam messages to be marked as spam but not moved to the Spam mailbox. If this is happening for you, choose Install Apple Mail Plug-In from the SpamSieve menu to enable the workaround.
• A small percentage of Apple Mail users are seeing a macOS 10.15 bug where a rule that is supposed to move messages to an IMAP or Exchange mailbox instead deletes them. If this is happening for you, make sure that your SpamSieve rule is set to move the messages to a local mailbox under On My Mac (as recommended in the Setting up Apple Mail section of the manual) rather than to a mailbox on the mail server.
• A small percentage of Apple Mail users are seeing a macOS 10.15 bug where moving a message to an IMAP or Exchange mailbox (either via drag-and-drop or via AppleScript, as SpamSieve does) instead deletes it. If this is happening for you, you can use the Change Settings command to set SpamSieve to (a) move messages trained as spam to a local Spam mailbox (this is the default); and (b) not move messages trained as good back to the inbox (you can instead copy them by Option-dragging or using the menu command).
• SpamSieve now includes an experimental feature to save backup copies of the messages that it has processed. This can help prevent data loss if you are one of the unlucky users affected by a bug in the macOS 10.15 version of Apple Mail that can delete messages when moving them from one mailbox to another. The bug is not actually related to SpamSieve and also manifests when it’s not installed. However, training messages with SpamSieve is a common reason that Mail would be asked to move messages, possibly triggering the bug. And since SpamSieve sees the messages, anyway, it’s in a good position to help mitigate the bug. For more information about backups and how to enable them, please see the Backing Up Messages section of the manual.
• If you are running into a bug in macOS 10.15 where Mail hangs for 10+ seconds during launch, the If Apple Mail Is Running Slowly section of the manual now describes how you can work around this by disabling and re-enabling SpamSieve’s plug-in.
• Worked around an Apple Mail bug that could cause the Preferences window to be blank on macOS 10.15, making it impossible to enable SpamSieve’s plug-in or to access other Mail settings.
• When installing the Apple Mail plug-in, SpamSieve will now warn you if Mail’s files are stored on a different volume than your home folder, which would prevent Mail from loading the plug-in on macOS 10.14 or later.
• If SpamSieve detects that macOS’s AppleScript system files are damaged, which can prevent training from working, it will now recommend that you reinstall macOS.
• After installing the Apple Mail plug-in, we recommend clicking the Quit and Show Instructions button. If you opt not to do this, the other button is now titled Continue rather than Cancel, to better reflect that the plug-in has still been installed and still needs to be enabled.
• There’s now an esoteric preference to mark Outlook messages as unread after filtering, to work around a mysterious issue where moving a message to another folder caused it to be marked as read.
• SpamSieve now logs to Console to help you detect inefficient regexes that slow down rule matching.
• Revised the Apple Mail and Postbox plug-ins for new macOS notarization requirements.
• Fixed a bug where training a message as good in Apple Mail could switch to displaying the inbox instead of moving the message to the inbox.
• Fixed a bug where SpamSieve could warn you that the Apple Mail plug-in was not enabled if Mail relaunched while SpamSieve was in the process of uninstalling.
• Fixed a bug where relaunching Apple Mail while SpamSieve was reminding you to enable the plug-in could result in a duplicate alert being shown.

SpamSieve 2.9.39 works with macOS 10.7 through 10.15 and requires an e-mail client. Older versions are available for older versions of macOS. In-depth information about SpamSieve is available in the manual.

If you enjoy using SpamSieve, please take a moment to review it on Product Hunt or MacUpdate or to mention it on Twitter, Facebook, or your own site. We’d really appreciate it.