How to Password Protect an Adobe PDFby Kefa OlangUpdated September 28, 2017
A PDF file is a high-quality document that is generally used to distribute platform-independent documents. Adobe Acrobat Pro enables you to password-protect your PDF documents so that other users do not have access to them. You may want to password-protect your PDF files if they contain personal and sensitive information and you want them available for either just yourself or specified people.
Download or purchase a copy of Adobe Acrobat Pro if you do not already have it (see Resources). You need the Pro version to password-protect your PDF files. Free trial versions are available that expire in 30 days.
Open the PDF file in Acrobat Pro. Click the "Secure" menu located on the tasks button bar. Click "Encrypt with a password" and click "Yes" on the confirmation dialog box to launch the Password Security Settings dialog box.
Select "Acrobat 7 and later" in the "compatibility" box and select the portions of the PDF file that you want to password protect. Select the "Encrypt all document contents" if you want to password protect the entire document.
Click the "Require a password to open document" check-box. When you select this option, only the people with the password will be able to open the PDF file. Type the password that you want to use.
Click the "Restrict editing and printing of the document" check-box if you do not want readers to make changes to your PDF file or print it. Type the password that you want to use. If you want to allow certain printing and editing options, select them in the "Printing allowed" and "Changes allowed" box.
Uncheck the "Enable copying of text, images, and other content" check-box if you want to restrict this feature. Click "OK" to save the changes. Your PDF file is now password protected.