Junk mail filter does not work

Junk filtering in Mail app is not working well, mostly if you have non iCloud accounts, like Gmail IMAP.

I will suggest to go to Preferences » Junk Mail tab, and click Reset. Also be sure to eliminate any Junk Rules (if you have » Advanced). This will erase all junk db and do a fresh start.

Mail marked as spam by your email service provider will be moved to the Spam mailbox on the server and mimicked on your Mac in Mail, if you have an IMAP account. Mail has nothing to do with those. If it is a POP account, I'm not sure how that would happen.

There is a setting in Junk filtering to Trust junk email headers. That should only move messages marked with a spam header into Junk, but not mark it as Junk. That will only occur if the Junk filters are on.

What email provider are you using (Gmail, iCloud, Yahoo..) IMAP or POP?

I will try this first instead only IMAP (have a time Machine backup updated a good idea):

Rebuild The Mailbox:

- Select the mailbox in the mailbox list of Apple Mail.

- Go to Mailbox Menu item and select Rebuild/

If it doesn't work:

Clear The IMAP Cache

- Quit Apple Mail.

- Go to the Library folder » Mail folder.

- Look the folder named IMAP-user@domain.com your are having issues.

- Move the folder to your desktop. (Don't delete the folder).

- Open Mail app, it will download all email from the IMAP server and rebuild your IMAP cache.

If it doesn't work

Reset mail to factory settings (credits to Linc Davis How to reset mail to factory settings.):

- Go to Library

- From the menu bar. Move the following items from the folder that opens to the Trash (some may not exist):

Caches/com.apple.mail

Saved Application State/com.apple.mail.savedState

Application Support/AddressBook/MailRecents-v4.abcdmr

Containers/com.apple.mail

Mail

Preferences/com.apple.mail.plist

Preferences/com.apple.mail.searchhistory.plist

Note: you are not moving the Mail application. You’re moving a folder named “Mail.”

Did any of the fixes they suggested for you work? Having same issue here. Thanks

Nealski wrote:

Sadly, they didn't stop the junk mail problem. Looks like I'll be doing a system reinstall sometime over the next month or so. :-(

Or you could just realize that your email provider just might be moving those messages to the Spam folder on the IMAP server which shows up in the Mail Junk folder.

Nealski wrote:

Sadly, they didn't stop the junk mail problem. Looks like I'll be doing a system reinstall sometime over the next month or so. :-(

If the junk mail on your Mac is coloured brown, Mail did it. If not your email provider did it.

I am having the same issue. There is a distinct change recently maybe when I upgraded my software earlier this month. It does not seem to learn when I mark something as junk also.

I am having the same issue as well. I have tried everything suggested here and have deleted and reset the filter several times and nothing. It is not learning what I mark as junk. It used to work. I have however tried logging in as a new user and setup my email and it is working under the new id. Now, I hate to just dump my old id. There is a lot of data and a lot of setup that I do not want to lose. I thought this might give someone who is smarter than me a clue as to what might be the problem. The problem is attached to the user id local to the Mac.

In my case it was google. I used the googlemail web interface and changed what google was marking as spam as not spam.