CasePeer's integration with DropboxSign supports the following file types:
doc, docx, pdf, ppsx, ppt, pptx, jpg, jpeg, png, xls, xlsx, txt, html, and gif.
The file name of the E-Signature Template must end in the lowercase file name extension. Using a file name extension with any capitalized letters is invalid (i.e. Document.pdf is valid, while Document.PDF and Document.Pdf are invalid.)