Enabling Automatic Updates for Windows

Windows XP

From the Desktop -

Click on the Start Menu

Click on Control Panel

Click on Automatic Updates

Confirm that the Automatic (recommended) option is selected

Winows XP - Automatic Update Settings

Windows Vista / Windows 7

Open Start menu,

Right-click on Computer and click Properties.

This will open System that will show basic information about your computer.

On the left sidebar, under See also heading, you will find Windows Update.

Clicking it will bring you to the Windows Update dialog box, now on the left sidebar click on Change Settings.

Confirm that the Install updates Automatically (recommended) option is selected

Winows Vista/7 - Automatic Update Settings