Want certain PDFs to always open in Illustrator
Most of the time I want my PDFs to open in Acrobat Pro. But for a lot of the files I work, I need them to be editable in Illustrator and to open in Illustrator. It used to be that when you right click on the file from the Finder, if you held down the option key, it gave the option to "Always Open With" and I could choose Illustrator. It would change the application file association and bam, problem solved.
For some reason this stopped working a while back. I suspect it was at some OS system upgrade, but I'm not entirely sure when it started. We're on OS X Yosemite at my work computer and I'm on OS X El Capitan on my home computer. The issue appears on all three different computers that I normally work with. You go through the routine of right-clicking on the file, selecting "Always Open With" and selecting Illustrator as my application, but the next time (and every time) I double click those files it continues to open in Acrobat instead.
We're using Illustrator CS5.1. Upgrading isn't an option. Is this a known bug with OS X Yosemite/El Capitan and AI CS5.1? Is there any solution?