Standalone users of Microsoft Outlook can password-protect the Personal Folders .pst file used to store all messages and other items.

I was wondering if there is some way that I can configure a password required to open Microsoft Outlook program. The thing is my computer can be accessed by a lot of people in my absence and I want to protect my emails to be read by another person than me.

Yes, it's possible to password-protect your Outlook data file. However, once Outlook is open, anyone with access to your computer can view the contents of your pst file. For this reason, you should secure your computer: when you step away, press Windows key + L to lock it. (And don't share your password!) Each user should have their own Windows user account.

You can password protect a pst, but don't count on the password doing much to protect your data from anyone who has access to your computer.

• If you check the Save this password in your password list box, you won't have to enter a password every time you use the PST file, but anyone walking up to your computer while you're logged on will also be able to use it.
• PST file passwords are very easy to crack, making them less than secure.
• If you use an Exchange Server mailbox security is tied to your Windows login.

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Note that pst passwords are not very secure as the password is easily removed (password recovery tools are listed in the Tools section at the end of this article.)

Many users ask for a method to password protect individual folders. Outlook does not offer a way to password protect just one folder in the *.pst file. It's all folders or nothing and you need to enter the password to open Outlook. However, the addins listed next will add this capability.

Password Protect Folder Tools

To password protect your Outlook *.pst file

To set a password on an Outlook pst file:

1. Go to the top level of your folder, where Outlook Today is found. The folder name may include "Outlook Today" or your email account name.
2. Right click on it and choose Properties (Data File Properties in Outlook 2010)
3. Click the Advanced button
4. Click Change Password
5. Leave the Old Password field blank and enter a New Password and verify password.

Leave the Save this password in your password list box unchecked. This prevents the password from being cached (otherwise, anyone can open the data file on this computer). You will need to type it each time you run Outlook.

If you are changing an existing password, type both the old and new passwords in the respective fields. When you open Outlook, you'll be asked for the password. This will prevent someone from opening Outlook and viewing your email. If Outlook is open, anyone using your computer can access your email - to protect it, you either need to close Outlook or lock the desktop when you walk away by pressing the Windows+L key.

Use a password you will remember. See Tools and More Information below for assistance with lost PST passwords.

See Bug in Outlook PST password protection for an explanation of how Outlook saves the password.

Password Protect Data File Tutorial

Password Removal and Recovery Tools