Hi, I just downloaded Adobe Acrobat Pro DC and I am using the trial version. I have an issue with the protection feature. I use "Encrypt with password" to protect my PDF files from editing or printing. The encryption works fine and it is perfect, but I just found the anyone can cancel this encryption and print or copy the contents of the file by just open the PDF file using FireFox browser. I tried it by myself and the file I encrypted was without any protection as I managed to copy and print the content of the PDF file. I don't know how this is possible, but now I am concerned about upgrading my account and buy Adobe Acrobat Pro DC to protect my PDF files. I hope you can explain the problem or the reason behind the ability of FireFox to decrypt protected PDF files
When you set security with Acrobat, then Acrobat should have warned you that third party apps may ignore the restrictions. Because it's true. The PDF rules say what the restrictions should mean, but some programmers don't like the idea of security, it conflicts with their ideas of freedom, and they ignore the rules. As Adobe's warning says, Adobe apps will respect the settings.