Windows Phone 7 like any other phones, allows you to lock your phone and also protect it with a password to prevent unauthorized use. You can automatically lock your screen on Windows Phone 7 and when you want to unlock it, you can set a password. This can be easily set from the settings option in Windows Phone 7.

From the Windows Phone 7 home screen, flick left to the Applications list and then press Settings.

In the settings, select Lock and Wallpaper.

How to Set a Password:

If you have not set a password for screen lock, you can set it by sliding the option against password.

You will be prompted to enter the 4 digit password, confirm the password and click done.

Changing the Password:

If you want to change the password, open the Lock and wallpaper option and click Change Password.

Enter the current screen password and then specify the new value you want to set. Once completed, click the done button.