Hello, I’m on Catalina latest version with Devonthink latest version. I’m trying to import messages from Apple mail, from an Office 365 mailbox with 17,000 messages. It is taking 40+ hours and failing, either by using Import ‘Mailbox’ or drag and dropping into Devonthink. Importing the Mbox from the apple mail folder fails as well. But… what I find, is that importing the mails using Eagle Filer, and letting Eagle Filer generate a new mbox file, and importing that into Devonthink, works in a about one hour … it cruises like it should be.
There is something wrong with the import process from Apple mail. It is pityfully slow and bares on being unusuable.
F.