Encryption is a means of scrambling data so that only authorized parties can access the document. It converts plaintext – the letters and numbers you’re used to reading – into a ciphertext – a series of random letters, numbers, and characters unreadable without the encryption key. Once you input the password, MS Word automatically converts the document back to plaintext so you, or whomever you’re sending the document to, can read it. While password protecting a file is a great way to hide sensitive data, it bears repeating that even the strongest cryptographic methods can be undone by human failures. Do not write your password down, share it via text message, or leave the document open when you walk away from your machine. 

How to protect a Word document with a password

  1. To password-protect a Word document, click the File Tab at the top of Microsoft Word’s interface. 
  2. Next, click Save As on the left navigation pane. This step will bring you to Word’s Save As page. 
  3. On the Save As page, click Browse. The Save As window should appear. 
  4. At the bottom of the window, click Tools > General Options… You should now be looking at a new window titled General Options that shows different options to secure your document.
  5. Under the Password to open and Password to modify fields, enter your preferred passwords and click OK. 
  6. Lastly, re-enter your password to open in the confirmation window and click OK.