I have occasionally encountered an error as well; sometimes it has been a space in the email title causing the problem. I suggest contacting ChungwaSoft support - they've been very good about working with me. I believe the product works via the Evernote email-in process. However, Evermail adds a terrific GUI to assist in tagging, filing and adding notes. Additionally, you can set it up to include both attachments and the original email as an attachment. Finally, if I'm not mistaken, the email will end up in EN as formatted, so HTML emails should be no problem.