On my laptop, using Vista, I often have a popup window when I open a PDF document. It says "Reading untagged document
This X-page document is untagged and must be prepared for reading. While the document is being analyzed..." And then I have "Reading Order Options" and two radio buttons "Read the currently visible pages only" and 3read the entire document".
Why is it like that? I never encountered that with Adobe whatever the operating system I was using. With the lastest Windows 7, I don't have that.