If your EMLX to MBOX conversion is resulting in missing attachments then it may be a few reasons. The first one is your conversion tool does not support full attachments and does not support proper processing. Some free tools have limitations and do not handle attachments. Second, your attachments are stored in a different format or location Then you can try a reliable tool like the Dailysoft EMLX converter tool. This is An interactive program that users find easy to operate singlehandedly. And also provide a free demo trial before purchasing. This tool is specially designed to preserve attachments during the conversion.