Cannot import free standing email attachment

I had a pdf document that originated in an email but has been taken out of that email. I had it in one EF library, but wanted to move it to a different EF library. When I tried to do this (trying both import drop pad and drag and drop methods), I got an error message about missing mail message. It would not import any part of the document. I removed it from the initial library, in case duplication was a problem but that did not help. I don’t understand why I was able to import it into the first library but not the second. It is no longer part of an email; it is now a free standing attachment in pdf form. What am I doing wrong? Thank you.

Nevermind, it’s in there now. Thanks.

That error happens when you import a message from Apple Mail but Mail had not fully downloaded the message. So the error was probably from the initial import into the first EagleFiler library. It wouldn’t happen when copying from one to the other. You can resolve the error by opening the original message in Mail—so that Mail downloads the attachments—and then importing it into EagleFiler again.

Many thanks!