I have combined several Word documents into a PDF and when I try to add a Header / Footer to add page numbers, I receive the message "An error was encountered while retrieving page content."
I have tried it several times. In the past it has worked flawlessly, but now, no matter what I try, the same message appears.
I have the latest updated version of Acrobat DC. The document is 151 pages. Everything is completely editable.
What OS do you work on?
If it is Windows,try to repair it once and see if that helps.