Mac Mail strange behavior

irwin1 wrote:

Perhaps 2-3 times a week, Mail randomly moves a message from InBox to another mail box. This happens only after I've read the message. Typically, I discover it's gone when I need to refer back to it. Usually it turns up in the All Mail folder and I can move it back to the InBox.

But until I find it, I panic, thinking the message has been deleted. I can find no reason for this. I've checked Rules and I've checked config settings, but can find nothing that would cause this. Fortunately, these messages don't show up in Trash folder, but still, it's seriously annoying. Ideas?

You can try— Rebuild mailboxes in Mail on Mac - Apple Support

if no resolve the next go to way of sorting issues is to delete the problem account and simply add it back in—

Add or remove email accounts in Mail on Mac - Apple Support