While this password is called the document open password in Adobe Acrobat, other PDF programs may refer to this password as the PDF user password or the PDF document open password.
How to Set a Document Open Password on a PDF
Some PDF readers may let you protect the opening of the PDF with a password but it’s usually specialized tools that include that option. There are also some PDF creators that have the option of creating a PDF user password. You can install the free trial of Adobe Acrobat to protect a PDF with a password, or of course, use the full version if you have it. Use the File > Properties menu and then the Security tab to find the Security Method option. Choose Password Security and then select the option in the new window called Require a password to open the document. Enter a password in that text field to create the document open password for the PDF file. Two other options for adding a password to a PDF is to use the Soda PDF or Sejda website. They’re very easy to use: upload the PDF file to the website and then enter the password you want to use. The Password Protect PDF page on Smallpdf.com is a similar website where you can stop a PDF from opening unless the password of your choosing is entered. You can use two PDFs on their site per day without paying.
How to Crack or Remove a PDFs Document Open Password
Document open passwords aren’t easily hacked but there are a few PDF password recovery tools that can do it via a brute-force attack, given enough time. The website Smallpdf.com is one example. After attempting to remove the password for you, it will ask you to enter the password yourself if it doesn’t succeed. Either way, it removes the password for you so that you can then download it back to your computer and use it as a regular PDF file. To simply remove the password, you can open the document in Adobe Acrobat. It will, of course, make you enter the password before you can move forward, after which you can follow the same steps as described above for setting the user password, but by choosing No Security instead of Password Security. While the Soda PDF website mentioned above is used for securing a PDF, the Soda PDF Unlock PDF page lets you remove the password. Unlike a PDF password cracker, you have to know the password. This website is useful if you’re just wanting to remove the password protection.
