How to protect a PDF document with a password


PDF (Portable Document Format) is a digital text document storage format designed to be read on various devices while maintaining the appearance and structure of the original. Apart from texts, it can contain links, hyperlinks, graphics, photos, and even videos and sound. Created by Adobe , it has become an open standard for exchanging documents, especially on the Internet. Its content can be digitally signed, but it can also be encrypted. Here we explain how to protect a PDF with a password . In this way, it is possible to prevent its content from being modified by third parties and even for certain data about the document to be hidden.

It is important to know that passwords for PDF documents cannot be reset, so it will be essential to remember them in order to make changes later. To begin, you have to open the PDF file in Adobe Acrobat . Once opened, it is necessary to enter the File menu and select Properties . Within the document properties, choose the Security tab . By default, all security options are usually allowed, and that is what needs to be changed to restrict use. First, you need to choose the security system in the drop-down box, which in this case is Password security. Once selected, a pop-up window opens that is used to configure the password. Within it, it is possible to establish which versions of Adobe Acrobat can open it, for example, from Acrobat X and later.


The encryption level (encryption) is usually AES 256-bit, although in other versions it is RCA 128-bit. Afterwards, the components of the document you want to encode are selected. The entire content of the document can be encrypted ; This means that search engines will not be able to access the file's metadata. Another option is to encrypt everything except the metadata , although it is also possible to encrypt only the attached files . Besides, it is possible to establish that you need to enter a password to open the document. In the password configuration there is also the section dedicated to permissions , where you can, firstly, restrict changes and printing the document using a password.

Then simply prevent printing or allow it by setting whether it is at high or low resolution. Likewise, you can prohibit all changes, allow comments or fill in the form fields, or allow anything except page extraction. Another option that can be marked within the permissions is to indicate whether the texts, images and other content will be copied . Finally, you can check the option to leave the content accessibility enabled by screen reader devices for the visually impaired. To conclude, press the OK button .