I am having trouble importing email from Apple Mail.

I am not sure where to post these questions… So I’ll start here.

I have the latest version of DevonThink Pro Office. I am using the latest version of Sierra (NOT High Sierra) on a Macbook Pro.

I am testing mail import and starting simple I picked a mailbox with 14,000 messages in it. Each time DevonThink hung - As reported by Activity Monitor. So I decided to start a little smaller and picked a mailbox with just 300 or so messages. I am using the Apple Mail Import option, This second attempt imported all but 60 of the messages. Each time the error message was. “Couldn’t write message file. Can’t continue import of mail message.”

Any suggestions?

Could you please choose Help > Report Bug while pressing the Alt modifier key and send the email to cgrunenberg - at - devon-technologies.com? Thanks in advance! In addition, are these messages located in local mailboxes or e.g. in IMAP accounts?