I have McAfee FRP ( Files and Removable media protection - 188.8.131.52 installed on my machine. I have encrypted some PDF files with it and when I tried to open the files I used to get following error " There was an error opening this document. Access Denied." Then I got to know the workaround on it as below. Disable Protected Mode in Adobe Reader 10: Click Edit, Preferences, General. In the left pane, deselect Enable Protected Mode At Startup. Close and re-open Adobe Reader.
Disable Protected Mode in Adobe Reader 11: Click Edit, Preferences, Security (Enhanced). In the right pane, deselect Enable Protected Mode At startup. Close and re-open Adobe Reader.
Although there is a workaround, I don't feel comfortable leaving it disabled. I would like a response from the team, if any patch available for it so that I can run both application simultaneously without any issue. Please note this is only happening with PDF files and not with any word , excel, ppt files.
It looks like your question is related to Adobe Reader. This forum is dedicated to Adobe's Activation core service, which is part of our Experience Cloud solution set. In order to make sure your question is seen by Creative Cloud experts (specifically, Adobe Reader experts), I'd suggest reposting your question on the Adobe Reader forums located at the link below.