I often receive PDF files from someone that has scanned them using a scanning photocopier. Sometimes alternate pages are upside down. i suspect this is due to an incorrect setting on the scanner. When I open the page manipulation tool, each time I select the little circle with the arrow beside a given thumbnail of a page, the page flips, but the tool then jumps back to page 1. I have to then scroll down to where I was and continue flipping pages. With a small document, it's not a big deal. But it becomes quite tedious with a larger document.