Occasionally I receive messages from recipients of pdf's I've created that when trying to open they get an error message to the effect that the file is damaged and cannot be opened.
The puzzling thing here is that it's not all the time with the same people.
Some of these have been from MAC users. I imagined that I had the problem solved by creating pdf's in the oldest version possible-Acrobat 4 (PDF 1.3), and with no security. Didn't work this last time (not sure if MAC, but pdf's are supposed to be "universal" right?).
Is there any conversion setting that I might be using, or changing that would cause problems? (I am checking to see if the most recent problem was MAC, and whether other recipients were able to succesfully open.)
The most recent pdf with problems was created from InDesign CS4.