I have a large document (a little over 200 pages) and about 50 pages are no longer visible in the document, but I can still see them in the pages panel. They are, however, blank in the panel, and there is a thicker stroke than normal separating the pages in the little image of the spread. When I double click on one of those pages in the panel, InDesign takes me to page 1 of the document. There is also a larger space than normal between the pages in the document where the missing pages are supposed to be. Have I lost them for good, or is there a way I can retrieve/see those pages?
You might try exporting the document to IDML and then saving it as an InDesign document.
Yay! I got my pages back....Thanks MUCH Alec!
Glad to help!