I have a PDF file I downloaded from the web. I get the banner message abbreviated above (the full message is "The file you have opened complies with the PDF/A standard and has been opened read-only to prevent modification."). The file was not bookmarked well and I would like to add further bookmarks for easy reference, but the read-only status prevents that. How do I turn off the read-only status? I have checked all the security settings I know of in Adobe Acrobat and see nothing to change there. There are no read-only settings turned on in the file properties in Windows either.
I am using Adobe Acrobat X (v 10.1.16) on a Windows 7 Home Premium system with Service Pack 1.
Thanks for your help.
In the preferences under Documents change the "PDF/A View Mode".