Have you ever experienced this? You setup some domain hosted email accounts in Apple Mail. But after a bit, several extra folders appear below the “On My Mac” area for each account. This has to do with how Mail sees your accounts on your particular hosting service. Here is the fix I found.
Here is what this problem looks like:
Mail makes a “ghosting folder” for each domain hosted account (it did not do this for my iCloud or Yahoo email accounts). I checked my server settings on my hosting provider for each account, but could not discover anything that I could tweak that would remove these folders. You can right-click on them and delete the mailbox, but they just come back after a while. I tried all kinds of things in the Mail app settings area plus a bunch of research online, but I came up empty, until I discovered an article online that gave me a solution.
Here is what you do with these “ghosting folders”. When they appear just click on the “ghosting folder” to select it, then go to the “Mailbox” menu and select “Use This Mailbox As”:
Since the “ghosting folder” was a “Trash” folder I just selected “Use This Mailbox As” – “Trash Mailbox”. Mail then puts the “ghosting folder” into the regular “Trash” folder. I did this for all my accounts and the Mail app moved each “ghosting folder” into the main “Trash” folder. I had to do it a couple of times for a few accounts, but so far they are all working correctly, no more “ghosting folders” in the sidebar of Apple Mail.
This is all done with IMAP accounts, I have no idea what it would do with a POP email account. And, I really have no idea why the “ghosting folders” are created in the first place nor do I know why this solution works, I am just glad it does.
Just another little experience with Apple Mail’s wonkiness. I am still running Postbox and Mail side by side, we will see how it goes.
I have seen articles by people complaining of this problem on other Mac blogs, so I know it is a fairly common problem. As far as I can tell, this is the solution, YMMV.