I've been trying to create an interactif pdf from the Book format in Indesign CS5.5 As there are thirty chapters I wanted to create buttons that as I click they take me back to the previous chapter or next chapter from every page. When I did trial exports, lets say chapters 1-12 or 15-25 etc they all worked. All the hyper links Bookmarks, cross referencing worked like a dream. The TOC works for every chapters as well. I created a button rollover state for following page, preceding page. They all work. But as soon as I export the entire book suddenly about 10 button links to go back or to chapters don't work. And there is no logic to why. For the last three days I've been driving myself nuts trying out different combinations. Re making the buttons, creating new links. And other than minimal changes (again with no logic behind them) I have the same broken button links. Is this a pdf bug problem ? Or have I missed something out completley. much help appreciated.