I have a huge mbox email archive file. It consists of around 110,000 emails and a size of about 4GB.
As expected importing this took around 8-9 hours. At the end though it showed on the counter of the correct email number import of 110k but in the folder only shows a count of 90k. Also about 10k of this emails have all the header info … From, Subject etc… but have 0 byte bodies. 2 questions.
How can I just try to import these 0 byte emails from the mbox file w/out redoing the entire import again?
Have you checked in your mail program that those messages actually have a body? Because if there is an error during the import this should be logged. On such a large message collection, I may not trust the Apple Mail database (I’ve had bad experiences).
If you have determined that there is a message body present on the mail application side, you could try to remove the corresponding document from the database (make sure to empty the Trash otherwise it will still be detected as a duplicate) and try the import again on just that message and see if it made a difference.