You can send any valid computer file along with your email. In fact, you can send multiple attachments. However, email is text and many programs and data files are in a format called binary. Different machines treat text differently, but can readily read text from other machines. However, binary files sent as text may get converted oddly and fail to work properly.
Text files sent as binary always work, however.
Since you can specify how attachments are sent, it seems clear that binary is the way to go and, in fact, is the default for modern email software. If you have problems, though, it might be a good idea to check. Call a tech for your software if you are not sure. By the way, there is no quick explanation of why the above problem occurs. Think of it like those transporter glitches that were always happening on Star Trek.