How to set password protection for PDF files?

php editor Apple introduces you how to set password protection for PDF files. PDF file is a commonly used document format. In order to protect the security of the file content, we can add a password to the PDF file. Setting password protection can effectively prevent unauthorized users from viewing or modifying file contents and protect the privacy and importance of files. With simple operations, you can easily add passwords to PDF files to ensure file security.

According to different needs, you can set two protection modes for PDF files.

In order to ensure that the file content can only be viewed by specific people, you can use the "Open Password" function of the PDF file to set access permissions.

First, we need to install the PDF editor, and then find [Password Encryption] under the [Protection] list in the menu.

(If you don’t have an editor, you can take a look at another tool introduced at the end of the article)

After the dialog box pops up, enter the password you want to set twice in the blank field. After clicking [OK], the password for opening the PDF file will be set.

After setting, as long as you open the PDF file, a dialog box will appear prompting "Please enter the password to open the file." It cannot be opened without a password.

If what needs to be protected is the content of the PDF file, such as preventing it from being edited at will, or copying or printing the file content, we can set "Restrict Editing" for the PDF.

Also in the PDF editor, find the [Protect] option, and then click [Restrict Editing].

After the dialog box pops up, enter the password you want to set in [Enter Password] and [Confirm Password];

According to your needs, you can also choose whether to restrict [Print Permissions], [Content Copy] and [Change Document] below the password box.

In the selection of [Change Document], the restricted content is further subdivided.

After selecting the above options, save and close the PDF file. When you open the file again, the "restricted editing" of the PDF file will take effect.

You can see that after "Restrict Editing", some options in the PDF, such as [Copy], [Print], and [Save] cannot be selected.

The options are all gray and cannot be clicked.

As mentioned earlier, if there is no editor, we can also use other tools to set the PDF opening password. Take Pepsi Niu PDF Password Recovery Tool as an example. There is an [Add Password] module in the tool, which can be used to set the "open password" for PDF files.

Tool link: Pepsi Niu PDF Password Recovery Tool

After selecting the module, import the PDF file and follow the prompts.

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