NB: To get the best result, your company templates need to be designed for the target application they are supposed to work with.
Word templates should be uploaded as .docx files
PowerPoint templates should be uploaded as .pptx files
Excel templates should be uploaded as .xlsx files
Your company templates need to be uploaded in Microsoft Office formats, but templates can be created in Microsoft Office formats to work with all office platforms e.g. Office 365, Google Drive, iWorks, OpenOffice, LibreOffice, and more.
Currently files must be uploaded as .docx, .pptx or .xlsx
(It is also possible to upload static PDF files)