Version 3.1 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 Junk mailbox. It’s quick and easy to control SpamSieve from within Apple Mail, Outlook, Airmail, MailMate, GyazMail, Mailsmith, 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.

SpamSieve 3.1 is a free update for those who have already purchased the SpamSieve 3.0 upgrade. If you’re using SpamSieve 2 and haven’t upgraded yet, the easiest way is to first let SpamSieve install the new version. At launch, it will show the Purchase window, and you can click the Check Upgrade Options button to get the upgrade discount without having to enter your old serial number.

The changes in this version are:

Highlights

• Made various changes to improve SpamSieve’s filtering accuracy.
• Previously, the Train as Good and Train as Spam commands in SpamSieve’s Message menu were disabled while you were in the app when there was nothing for them to apply to, i.e. if no messages were selected in the Corpus or Log. To reduce confusion, since some people thought these commands were meant to be used from within Apple Mail or Outlook, they are now always enabled but will open the Train as Good/Spam section of the help when not applicable, as that will direct you to the various ways that you can train SpamSieve from within your mail client.
• If macOS incorrectly reports that SpamSieve is damaged when installing or updating the app, we now have a Download Fixer tool to help.
• SpamSieve no longer triggers the “find devices on local networks” prompt on macOS 15. It never needed that access, anyway. If, for some reason, you still get the local network access prompt, it’s fine to click Don’t Allow.
• SpamSieve is once again localized in Korean.

Blocklist and Allowlist

• If SpamSieve hangs due to a bug in Swift Regex, it is now able to report the problematic pattern and string, so that you can temporarily disable the offending rule and so that we can make a bug report to Apple.
• Added some protections to help prevent rules from malfunctioning if the rules database is damaged.

Log

• When you copy a log entry as text, it now shows more information about the corpus and rule changes.
• If there’s an error reading an inessential part of the log database, SpamSieve will now just log the error instead of preventing you from using the app.

Apple Mail

• If you’re using Proton Mail, we recommend using the Move it to the Trash if the spam score is at least setting to have SpamSieve move all spam messages to the Trash instead of to the Junk mailbox. This will ensure that Proton Mail removes the spam messages from the special All Mail mailbox.
• Fixed a problem where, if you flagged a good message at the same time SpamSieve was filtering it, the flag could be overwritten.
• Worked around a Mail bug where it could lose a message if you were manually refiltering messages that were already in the Junk mailbox.
• Fixed an issue where, if a mail account was reset or Mail’s database was rebuilt, SpamSieve might reprocess old messages if they were still marked as unread.
• Worked around a Mail bug that could cause a modal error to be reported (and block filtering and use of the app) when moving a message on an Exchange server.
• The Select Mailboxes to Filter… sheet now prevents the selection of additional sent and notes mailboxes, as these do not receive new messages that should be filtered.
• Added some diagnostics to help track down a Mail bug that can cause messages to be inappropriately flagged orange when using the Mail extension.
• The diagnostic report now includes additional information for troubleshooting problems with Mail’s database and Mail extensions.

Microsoft Outlook

• When there’s an error processing an Outlook message, SpamSieve now reports the account name and folder, not just the subject of the message.

General

• Updated the Dutch, French, and German localizations.
• Fixed an issue where SpamSieve could get confused if you corrected a mistake but the mail server had changed the message data in between the prediction and the training.
• Tried to work around a macOS bug that could cause it to incorrectly report the SpamSieve application file as damaged.
• The × button in progress views now has an accessibility label.
• When trying to open a database file that’s damaged, SpamSieve will now move it aside (saving it for diagnostic and recovery purposes) and start a fresh database automatically, rather than blocking the app from launching.
• Fixed a problem where database errors caused by the disk being full were not handled properly because macOS was incorrectly reporting the error.
• Removed various code that is no longer used.
• The diagnostic report now includes information about the app’s logs, the crash logs folder, and components that could cause AppleScript errors.
• SpamSieve is now built with Xcode 16 and the macOS 15 SDK.

Documentation

• Worked around a bug in macOS 15 where sometimes the system help viewer wouldn’t open to the right help page. SpamSieve will instead open help files in the user’s Web browser.
• Improved the following sections of the manual:
  • Checking the MailMate Setup
  • Checking the Outlook Setup
  • Correct All Mistakes
  • Hiding Special Gmail Mailboxes From IMAP
  • How can I copy my training data to another machine?
  • How can I rebuild Apple Mail’s database?
  • If Apple Mail Is Running Slowly
  • Move it to the Trash if the spam score is at least
  • Rescuing Good Messages Caught By a Server Filter
  • Setting Up a MailMate Drone
  • Train as Good/Spam

AppleScript

• Optimized the scripting support so that it is now possible to access the entire contents of a large corpus without overwhelming AppleScript, as demonstrated here.
• The training script commands now report an error if you forget to supply the message data.

SpamSieve 3.1 works with macOS 10.13 through macOS 15 and requires an e-mail client. Older SpamSieve 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 MacUpdate or to mention it on Twitter, Mastodon, Facebook, or your own site. We’d really appreciate it.