When importing mail from Apple Mail, EagleFiler may report a Missing Apple Mail Messages or Missing Apple Mail Attachment error. This indicates that the message had not been fully downloaded to your Mac. You should tell Mail to download the messages and then try the import again. There are several ways to do this:
For a small number of messages that are missing attachments, it’s easiest to open the messages for viewing in Mail. This will trigger Mail to fully download them. You can select the error(s) in EagleFiler’s Errors window and Option-click the Reveal button. This opens the message files in Mail. Once the attachments have loaded in the message windows, you can close the windows and then try the import again.
For a larger number of messages, you can select all the messages to import in Mail and run the Download Apple Mail Messages script. Once this has completed, press the capture key with the same messages selected to import them.
For very large numbers of messages, the script can take a while. A faster option is to Option-drag and drop the entire mailbox to the On My Mac section of Mail’s mailbox list. This will create a local copy of the mailbox with all the messages fully downloaded. (Do not drag messages to an On My Mac mailbox, as that could cause data loss.)
Note: Mail does not allow you to drag special mailboxes such as Inbox and Sent. To make a local copy of messages in one of those mailboxes, first create a new mailbox on the same server. For example, if you want to import the inbox messages from 2025, you could create a new mailbox called Inbox2025. Drag the messages in that date range from Inbox to Inbox2025. This should be pretty quick, since it’s just moving the messages on the server. Once that’s done, drag Inbox2025 to On My Mac. This may take a while, since the messages are all being downloaded to your Mac. Then select the messages in On My Mac ‣ Inbox2025 and press the capture key to import them to EagleFiler.
See also: Importing Attachments From Apple Mail.