Look for third-party apps like View Source, Source for Webpage, Source Browser, and similar apps that allow you to view HTML source code. Outlook is designed to support only a sub-set of HTML 4, so some HTML tags are simply ignored. You need to add the URL or the reference link of your PDF file to the element. A link to the PDF is okay if you … For the debrief below, use the codes from my web page example that I asked you to print out on page 2 of this document. End Results to View HTML source codes . Now onto the PDF to HTML code. The Wrong Way To Edit HTML Code. Another way of adding a PDF file to your HTML document is using the