How to Password Protect a PDF in Open Office Mar 29, 2024 — To set a password for any PDF file, select the file from the File menu and in the drop-down menu, choose Preferences›. Then go to the Password Options area. Note: this is not a standard setting in Open Office. How to Password Protect a PDF on Mac (for free) — How-To Geek You can set a password for an individual file, a system wide group of files, or even all PDF files (as opposed to just the ones in a ZIP file). When you've set a password, it's a good idea to keep the password in a hidden location to prevent losing it. How to Password Lock a PDF If you want to password protect a PDF file, so you can't view or open it, and no one else can, then this is the easy way.