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Every Monday we show you how to do something quick and cool using built-in OS X utilities such as Terminal, Apple’s command line application. These easy hacks can make life better and simpler, and don’t require any knowledge of coding — all you need is a keyboard to type ’em out!
Securely storing certain information in the universal PDF format can be a good thing — after all, your bank, insurance, or other personal information could be contained within PDF documents. That information, if it got into the wrong hands, could compromise your personal security. Lock down your PDF documents using this simple trick in the Preview application.
To begin encrypting a PDF document that you’ve already created, open the file with the Preview application. Next, perform these steps to encrypt the PDF document that you just opened:
Hold down the option key.While holding down option, click the File menu. Note that Duplicate has changed to Save As.Click Save As.Check the option for Encrypt, then enter and confirm your password to encrypt the document.
This is the easiest way to encrypt a PDF document that you have already created or have lying around on your disk.
The next time that you attempt to open the document with Preview, you’ll see that you’re now required to enter the password that you saved the document with before the contents of the PDF are visible to the reader. This adds an extra layer of security when emailing documents or storing them on an unencrypted computer.
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