ValidSign supports the following documents / file types: .pdf, .doc, .docx, .txt, .rtf and .odt. We also support any document that can be printed from a Windows application (e.g. .xls, .xlsx, .ppt, .pptx, etc.) via the ValidSign printer driver.
What you should keep in mind is that we automatically convert all documents you upload to .pdf. In the conversion, it may happen that not everything is converted correctly and that some things are not aligned correctly. We therefore recommend that you convert your files to PDF in advance before uploading them.