Hi lorizb,
On the basis of the information you have provided, it seems to me those pages either might be Scanned Pages or Pictures, which could give this kind of issue. If this would have been related to the whole document it would have been possible related to the access rights on the file.
Let us know if you have any further questions. If you want us to take a look of the file, you may share the Dropbox link.
Regards,
Tariq Ahmad