1. Select the Start  button, then select Settings  > Update & security  > Windows Update . If you want to check for updates manually, select Check for updates.
2. Select Advanced options, and then under Choose how updates are installed, select Automatic (recommended).

To turn on automatic updates in Windows 8.1:

1. Open Windows Update by swiping in from the right edge of the screen (or, if you’re using a mouse, pointing to the lower-right corner of the screen and moving the mouse pointer up), select Settings  > Change PC settings > Update and recovery > Windows Update. If you want to check for updates manually, select Check now.
2. Select Choose how updates get installed, and then under Important updates, select Install updates automatically (recommended).
3. Under Recommended updates, select the Give me recommended updates the same way I receive important updates check box.
4. Under Microsoft Update, select the Give me updates for other Microsoft products when I update Windows check box, and then select Apply.

To turn on automatic updates in Windows 7:

1. Select the Start button
   

   . In the search box, enter Update, and then, in the list of results, select Windows Update.

2. In the left pane, select Change settings, and then under Important updates, select Install updates automatically (recommended).
3. Under Recommended updates, select the Give me recommended updates the same way I receive important updates check box, and then select OK.