I downloaded some open XML specification PDF/A documents (PDF version 1.4, created using MS office word 2007) from w3c website. I wanted to use the text highlighter tool to highlight the important portions so that I can refer to them later quickly but found that the tool is disabled. I even tried converting the PDF to a newer version (1.6, 1.7) and to PDF/X etc. but nothing helped.
When I see the Security Method it says "No Security" and everything (printing, editing, commenting) is "Allowed".
I don;t know how to enable the tool. Other editing related tools are also disabled (Text edit, Add Sticky note etc. )
Is this document protected, if yes then why is it saying "No Security", and is there a way to unprotect it so that I can highlight the text in it.
I have the same problem (Highlight and other tools grayed out, no security restrictions in place), but when I try to find Edit>Preferences>Document to turn off PDF/A, that choice does not appear in the menu. The only mention of PDF/A in the help guide for my version of Acrobat is in "new features" and it does not tell me how to find this. How can I enable editing? I did not originate the document.