I have this same issue. I recently updated to macOS Catalina 10.15.2 (19C57), newest version of Adobe InDesign CC. All my links appear correct in preflight panel, and I am also unable to export a .pdf (interactive); similar to the issue Aidanj is having.
• I exported an IDML, and ALL links disappear, so that doesn't seem to work.
• I open the original .indd document, and packaged it (including links, fonts and .imdl). I then opened the new InDesign file-copy located in the packaged folder, and successfully exported a .pdf (interactive).
The message I am receiving when exporting a .pdf is: "Indesign “this document contains links to files/URL(s) that are not accessible. Please check your network connectivity or the original source of content."
Hi everyone.
I was having the same problem for almost 2 months.
This solved my problem:
Go to your system preferences > security and privacy > files and folders > click all the boxes under Indesign and Illustrator
