I have “Enable junk mail filtering” unchecked and turned off, and I had deleted Mail’s old Junk folder so I could use SpamSieve’s Spam folder instead, however this morning while I still had new messages marked as Spam by SpamSieve in the Spam folder, I also had a newly created Junk mail folder with two messages in there. How can I delete this Junk mail folder so that it doesn’t come back and have new messages marked as junk and sent to there instead of SpamSieve’s Spam folder?
iCloud always creates a Junk mailbox which holds the spam messages that are caught by Apple’s junk mail filter (on the iCloud server). There’s no way to turn this off.