How does WORD enter into this. You simply print from AutoCAD to the Adobe PDF printer. There may be a PDF Maker for AutoCAD with AA9, but I am not an AutoCAD user and don't remember off hand. Just exactly how are you creating these PDFs (particularly you have mentioned WORD in you post)?
Some of the pages originated from AutoCAD, Some Originated from Word. The pages alone look fine. The pages assembled together presents the "disappearing" pages (It looks to be only the ones from AutoCAD that are partially vanishing). The final document has the application listed under properties as "Acrobat PDFMaker 9.1 for Word"
Actually the word part and the final document are not created by me, but by an associate. I will talk to them tomorrow to see exactly how they create and assemble the document. The jist is the pages look fine separately, but assembled some pages are partially "vanished". Very odd.
The first pages are printed from Word (using adobe print driver). the document is opened in Adobe Acrobat 9.5.5 pro and the CAD PDF files are inserted and document saved. note the document is stored on a network drive. The document at this point looks fine, all pages are fully there. Only after some time (a day or so) come back to the document and then the CAD pdf pages are partially vanished. The partial pages seem to be stable, in other words - the vanishing doesn't seem increase.