I have Acrobat Pro version XI (11.0.11). I work with construction plans that are digitally signed by an engineer. As part of my work, I add a watermark using the "file" option. This was never a problem when using version VII, but I recently upgraded to version XI and now it won't let me add the watermark. It says I don't have sufficient user rights. I tried even inserting a text version of a watermark with the same results. Can anyone help?