How Can I Move Mail to a New Mac
My wife picked up a '17 iMac last week replacing her '13. She's running High Sierra due to CS6 limitations. All is fine on the system, but Mail. I've tried numerous ways to move the mail from her old machine to the newer one to no avail. If I must get into detail of what I've tried, but didn't want to convolute the post.
Aside from Migration Assistant, what is Apple's no fail way of moving mail from one machine to another?
iMac Line (2012 and Later)