How to protect PDF files from being modified at will?

php editor Banana teaches you how to protect PDF files from being modified at will. PDF is a commonly used document format, but sometimes we want to ensure that the file content is not modified at will. By setting password protection or adding a digital signature, you can effectively prevent others from modifying your PDF files. In addition, you can also use PDF editor software to add security watermarks, restrict printing and copying, and other functions to further enhance file security. Taking these measures can effectively protect the integrity and security of PDF files, allowing you to share and disseminate important files with more confidence.

In order to "restrict protection", we need to utilize a PDF editor. Taking the editor I use as an example, first open the PDF file, select the [Protect] tab, and then click [Restrict Editing].

After the [Restrict Editing] interface pops up, enter the password you want to set twice under "Edit Password", and then select the options you want to restrict under "Document Permissions" as needed. You can set printing, content copying, and modification. Document and other permissions;

Under the "Change Document" option, you can further refine the restricted document editing content;

After the restriction option is selected, click [OK] and "Set successfully" will be displayed. After saving the PDF file, the "Restrict Editing" will be set.

After setting up, the PDF cannot be edited or changed, and most of the options in the menu bar are gray and cannot be clicked.

If you need to edit the PDF file later, you only need to lift the "restriction protection".

Similarly, first find the [Protection] tab, and then click [Delete Security Settings];

After the [Prompt] dialog box pops up, enter the originally set password in the password field. After clicking [OK], the "restriction protection" of the PDF file will be lifted.

It can be seen from the above operations that to remove the "restriction protection" of PDF, you need to enter the originally set password, so when setting the password, remember to remember or save the password, otherwise you will not be able to use the PDF editor. Restrictions have been lifted.

Of course, if you accidentally forget it, don’t worry, because we can also use other tools to solve the problem. Take the Pepsi Niu PDF password recovery tool as an example. You can directly remove the "restriction protection" of PDF without entering a password.

First click [Unrestriction] in the tool and then proceed to the next step;

Tool link: Pepsi Niu PDF Password Recovery Tool

After entering the next interface, import or directly drag the PDF file with "restriction protection" set, and then set the "output directory" as needed. You can also choose the default address without changing it, and finally click [Start] to start. Lift restrictions.

The PDF file after the restriction is lifted will be saved as a new file and will not replace the original PDF. Click [Go to View] to open the folder where the new PDF is located.

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