Set Permission Password Set Password — Why should your PDF files be protected? If you have installed Adobe Acrobat Reader, you need to install one of the following Acrobat Plug-ins, according to my recommendation, in order to prevent the user from copying PDF files: (For instructions to install a plug-in, visit.) — “Acrobat Viewers. — “Acrobat Reader For Chrome. How to protect PDF How to protect PDF — Stack Overflow Why PDF files need protection? When you copy a PDF file from the computer to a portable device such as a flash drive or USB thumb drive, Adobe Reader will copy the file as-is, without protecting it from reading. While one can make an arbitrary copy, it is impossible to make the file protected. How do I prevent Adobe Acrobat Reader from opening the PDF file? 1. Go to … Adobe Acrobat Reader 2. Go to … Adobe Acrobat Settings 3. Select … PDF Protection 4. Click protect PDF to Protect PDF… How to print PDF files? 1. First make sure that it is not open. 2. Then drag the PDF file into the Open With pop-up. 3. Click Open to choose which PDF file to open. Do not open PDF files you downloaded from sites such as EZS hare, which do not protect PDF files. Deciphering Encrypted Files How To Encrypt Or Decrypt Encrypted Files? The way to decrypt an encrypted file is easy. All you need is a program like WinRAR or WinZip or Windows Encrypt or, and for this purpose, the name of the program is the same as the encryption scheme. For example, in Windows 7, you need to first run File Explorer to open the Encrypt Files dialog box. Then, you will see something like this: File Encryption Format You will need to scroll down and see the Encryption algorithm in the Name field. This is the name of the program which has changed the filename or folder name. Also, the Program should be in a different language as well, like this: So, now you need to choose the one that matches this.