I use Adobe Acrobat Pro 10.1.16 with Mac OS 10.11.1
I want to open a PDF, just as in Yosemite OS. The answer is “Impossible to write in this file; perhaps is it being used”. The file file is actually NOT used. Is there an issue?
Acrobat X is not compatible with Mac OS 10.11 System requirements | Acrobat family of products—older versions (XI, X, 9). Make sure you use the application in a compatible environment to make it fully functional.
I have a similar set up ad encountered the same error message.
I have now new mac air with OSX 10.11.3 and installed Acrobat Pro X. It works except for (quite) a number of functions, such as exporting the pdf to png or tiff (or similar format). Gives an error message, short of disk space (page 1).
On my old macbook (with OSX 10.11) these functions still worked, but I assume that is because it followed all the updates and possibly internal setting were kept.
It is clear now, need to fund Adobe to get an upgrade.