PDF files are already fairly secure – they make it very difficult if not impossible to change the content within, and with the use of watermarks and similar features, it’s relatively easy to make sure nobody steals what you’ve created.
If you are looking for an even more secure setting though and want to keep your file from prying eyes entirely, you can set a password fairly easily, especially if you have access to Acrobat DC (which has a free trial version if you don’t want to pay). Other versions of the Acrobat software also support this function though the steps to protect your file are different.
Tip: Beware of online password-tools. There are some online tools that also allow you to password-protect your file. Not all of them are legitimate, and in order to password protect the file in the first place, you need to upload it to what could be an unsafe server. Always think carefully before using services like that.
There are two types of passwords that you can put on your PDF – an access password and a permission password. The former prompts a user for a password when it is opened – in other words, you can’t look at it at all unless you have the password.
The permission password can restrict users from doing things like printing, editing, copying and more. In this case, the receiving user does not need to have the password – they can see and use the PDF without it; however, they can’t access the restricted functions. To do so, they would need the password.
Tip: A PDF can have both types of passwords at once, and it is highly recommended that they be different from one another. Additionally, observe the usual rules on setting a secure password – use letters, numbers, special characters, etc, and make sure your password is eight or more characters long. While Acrobat DC won’t force you to stick to these rules, it is highly recommended that you do to make sure your file is well-protected.
In order to password-protect your PDF using Acrobat DC, follow the steps below:
- Open Acrobat DC
First, open Acrobat DC and make sure you have an active license, be it free or paid.
- Open the file
Simply open the file in Acrobat DC by either dragging and dropping it or using the Open function from the menu.
- Set the Password
Click first on “File” and then on “Protect using password”. You’ll be prompted with a popup window that lets you select from some options. First, you can pick which type of password you want to set. As mentioned, a Viewing or Access password will require the password every time a user wants to open the file, while an Editing or Permission password only stops them from performing certain actions, and the password is not actually required.
Tip: Especially when setting an Access password be careful – if you lose it, you will NOT be able to retrieve it, nor access the file again without it. Always keep a non-password-protected backup copy somewhere safe.
Then, you need to set the actual password – be sure to pick something safe, but also something you can remember without writing it down. When you are happy with your options, click on Apply – a message will appear that your file is now protected.
Tip: Click on “More Options” and then “Advanced Password Protection” on the screen where you can set the password to select from options like restricting printing, editing or copying. You can even decide whether a user can, for example, only print low-resolution copies of the file – or you can forbid it entirely. Similarly, you can restrict whether a user can change, delete or rotate pages, simply fill in forms, or leave comments. Once you are done setting your permissions, you’ll be prompted to choose an encryption level – select “Encrypt All Document Contents”, set your password and click “Ok”. Once again, you will see a notice saying you’ve successfully protected your file.