I have to send .jpg attachments of designs to customers for their approval. When I view the sent attachment, it just shows a small box with a red "x" in it. Sometimes the customer will be able to open the attachment and sometimes they can't. Is there a better way to be sending these .jpg files? Is there a setting that I need to change so they can view the attachments? Maybe I need a program like Adobe Acrobat to send my designs. Could you help me?