A password is a secret word or string of characters that is used for authentication, to prove identity or gain access to a resource (example: an access code is a type of password). The password should be kept secret from those not allowed access. A pdf open password is the password used to restrict the opening of a pdf file in Adobe Acrobat, So if you have some pdf files that you won’t allow other people to open, you can encrypt pdf file with open password. And how to encrypt pdf file with open password, Advanced PDF Tools Command Line will tell you.
Step 1 click the following link to download Advanced PDF Tools
https://www.verypdf.com/pdfinfoeditor/advanced_pdf_tools_cmd.zip
please unpack it when download is finished.
Step 2 launch the MS-DOS command prompt window. Because the command line is bound to be operated under the MS-DOS environment. The procedure is easy, and the following pictures will guide you.
1) click “start” and then go to “Run”
2) input cmd into the following
3) press “ok”, you will find MS-DOS command prompt window popping up
Step 3 input command line to encrypt pdf file with open password
it goes below
pdftools.exe -i C:\*.pdf -o D:\*.pdf -S openpwd=xux -S keylen=2
where
- -i is to specify a pdf filename or a directory for input,
- -o is to specify the pdf file name for output,
- -S openpwd=xux to encrypt an open password as xux
- -S keylen=2 refers to 128 bit AES encryption (Acrobat 7 or higher)
when the input is done, press “enter” key, you will see
Step 4 open the file to check if opening the file an open password is needed
and you can type the open password xux to open it
So, when you open the file, an open password is needed, that’s to say, you are successful in encrypting pdf file with open password.