Microsoft Outlook uses the proprietary PST file format to store information. PST files hold all of the data contained inside your Microsoft Outlook folders, including both your incoming and outgoing emails. Encrypting a PST file can prevent unauthorized individuals from accessing the sensitive information that email communications often contain. Fortunately, Microsoft includes PST file password protection in Outlook.
Launch Microsoft Outlook.
Click the "File" tab at the top of the screen.
Scroll to the "Account Settings" icon and click it to expand the additional options sub-menu.
Click the "Account Settings" option.
Click the "Data Files" tab at the top of the window.
Click the PST file that you wish to encrypt.
Click the "Settings" button.
Select the "Change Password" button.
Type a password into the text field next to "New password," then retype the password into the text field next to "Verify password."
Click the "OK" button to encrypt the PST file.
- Use a password that is at least eight characters long, including a combination of letters and numbers.