This issue started occurring for me recently and I urgently need a resolution to the problem as it prevents generation of new books for product team reviews. Specifics: * Until recently I was able to save and generate a book file. Changes were made to various .fm files that are part of the book and now when you attempt to update the book, this error is returned. * I did a clean install of Framemaker on a second machine and the same error occurs for me. * Other users appear to be able to open and regenerate the book without issue on their machines. * Other books appear to generate correctly for me.