Since all of the documents Fastoche generates are PDF, we require your letterhead to be in PDF format. If you have a Microsoft Word format letterhead, there are options to export or print to PDF. Letterhead PDFs must not have security enabled such as passwords.
For logo files we currently support JPEG and PNG files. If your logo is in another format, you will need to convert it to one of these two in order for it to work correctly in Fastoche.