How to prevent changes to PDF files?

How to prevent changes to PDF files? This is a concern for many users. In our daily work and life, we often use PDF files to share and disseminate information, but sometimes we worry that the files will be maliciously tampered with by others. In order to ensure the security and integrity of files, PHP editor Yuzai has summarized several simple and effective methods to prevent PDF files from being changed, making your files more secure and reliable.

●Achieved by restricting passwords

We all know that usually, PDF files cannot be edited when they are opened through a browser or PDF reader. However, if we use a specialized PDF editor to open the PDF file, we can edit it easily. If the file content cannot be changed even in the editor, we can also protect the PDF file by setting a "restriction password".

Set the "restriction password" and use the PDF editor to complete it.

Open the PDF file through the PDF editor, and then click [Restrict Editing] in the menu tab [Protection] interface to set it.

After the [Restrict Editing] dialog box pops up, select [Prohibit Changes] in the [Change Document] list of [Document Permissions], then enter the password you want to set twice in the password field, and finally click [OK] It's set.

In this way, the PDF file cannot be edited and changed when it is opened in the editor. You need to use the password to remove the "restriction password".

You need to edit it later, as mentioned above, just remove the "restriction password".

After opening the PDF file through the PDF editor, click [Delete Security Settings] in the [Protection] interface on the menu tab. After the dialog box pops up, enter the originally set password in the password field to cancel it.

As can be seen from the above operations, you need to enter the original password to lift the "restriction", so remember to save it when setting the password.

What should I do if I forget it accidentally? In this case, we can take help from other tools.

For examplePepsi Niu PDF Password Recovery Tool can directly remove the "restriction protection" of PDF files without a password. After selecting the [Unrestriction] module in the tool, and then importing the PDF file that has forgotten the password, it can be released with one click.

●Achieved by converting format

In addition to using "restriction protection" to prevent modification of PDF files, if there are no format requirements, we can also convert PDF files into image formats, so they cannot be edited or modified.

If you want to convert PDF files into images, you also need to use a PDF editor.

After opening the PDF file through the PDF editor, click [To Image] in the [Convert] interface of the menu tab to select the image format you want to convert, and then perform the conversion.

●PDF conversion tool

If there is no PDF editor, we can also use PDF conversion tools to convert to image format.

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