rc/mime/ms

   1 .doc    application/msword
   2 .docx   application/vnd.openxmlformats-officedocument.wordprocessingml.document
   3 .dotx   application/vnd.openxmlformats-officedocument.wordprocessingml.template
   4 .potx   application/vnd.openxmlformats-officedocument.presentationml.template
   5 .ppsx   application/vnd.openxmlformats-officedocument.presentationml.slideshow
   6 .ppt    application/vnd.ms-powerpoint
   7 .pptx   application/vnd.openxmlformats-officedocument.presentationml.presentation
   8 .rtf    application/rtf
   9 .sldx   application/vnd.openxmlformats-officedocument.presentationml.slide
  10 .xls    application/vnd.ms-excel
  11 .xlsx   application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
  12 .xltx   application/vnd.openxmlformats-officedocument.spreadsheetml.template