When sending the attachment make sure that you send the document with a file name that is compatible with a windows computer. Windows to Macintosh File Transfer Windows to Macintosh file transfers are generally much easier to accomplish than Macintosh to Windows file transfers. Applications that pose difficulty in cross platform files are Canvas documents. There are probably others. Save as to change the file to a Macintosh compatible version before quitting.
File transfer using a floppy or Zip disk is easy and the requires the same set-up discussed above.
Make sure the file name is eight characters or less and has a Windows compatible extension.