There are two ways to protect a PDF file: owner password and user password. We will explain the purpose of each of them and show how to apply them to your PDF files.
Owner Password or Permissions allows you to apply permissions to the PDF file. For example, if you do not want to allow printing of a PDF file or extracting pages, you can choose what you want to allow rather than allow and apply the owner password to the PDF file. The owner password can also be called a master password. This is what allows you to change these permissions.
User or Open password allows you to require the user to enter a password even to view PDF. If they do not enter the correct password, the PDF file will not open.
There are several online services for protecting PDF files, such as PDFBeaver, but if you want to add a password to a confidential document, you are probably not comfortable uploading it to an unknown service. So, in this guide we will focus on the best offline mode.
We looked at how to create a password-protected PDF file in Microsoft Word, but this only adds the user password. There is no way to add an owner password. We did some research and found that the best option for protecting your webpage to PDF files offline is the free LibreOffice office suite. We will show you how to password protect a Microsoft Word or LibreOffice Writer document and how to create a password-protected PDF file from the document.
NOTE. We use the Word file in our example, but you can do the same with LibreOffice Writer documents (.odt files). You can also open PDFs in LibreOffice. They open in LibreOffice Draw, even if you use Writer, Calc or Impress, but the procedure for protecting them with a password in Draw is the same as in other LibreOffice programs, and is described in the section “How to Convert a Document to a Password-Protected PDF File” below. You will convert an unprotected PDF file to a password protected one.
How to convert a document to a password-protected PDF file
You can also convert a Word document or a LibreOffice document to a password-protected PDF file and apply user and owner passwords to it. To do this, open the document, and then select Export to PDF from the File menu.
In the PDF Options dialog box, click the Security tab. In the section “Encryption and resolution of files” initially there is “Open password not set” (user password) and “Access password not set” (owner password). To set these passwords, click Set Passwords.
In the “Set Passwords” dialog box, in the “Set Open Password” section, double-enter the user password that is required to view the PDF file. In the “Set access password” field, enter the owner’s password, which will not allow printing, editing or extracting the contents of the PDF file. Click OK. You will return to the “PDF Settings” dialog box, and the status of the set passwords will be displayed under the “Set Passwords” button. If you decide to set a permission (owner) password, the parameters in the right part of the dialog box will become active. If you do not want anyone to print a document or make any changes to it, select “Not Allowed” in the “Printing and Changes” section. If you just want to limit the type of print and possible changes, select another option in the Print &Change section.
If you do not want anyone to copy the content from your PDF file, make sure the “Enable copying of content” checkbox is cleared. In order to ensure accessibility, it is recommended to leave the “Enable text access for accessibility tools” checkbox checked. Click Export. In the Export dialog box, navigate to the folder where you want to save the password-protected PDF file. Enter the file name in the “File Name” field and click “Save.”
If you assigned an open (user) password to the PDF file, it will be requested the next time you open it. You will see “(PROTECTED)” to the right of the file name in the title bar, indicating that it is an encrypted PDF file.
If you applied a permission (owner) password to the PDF file and decided not to allow printing, you will notice that the “Print” option is not available when you click the “File” tab.
The procedures for adding open and permitted passwords to a document and converting the document into a password-protected PDF file you can also convert HTML to PDF and process of protecting is same in LibreOffice Calc, Impress, and Draw.
PDF Beaver 