In the Run dialogue box type: ‘services.msc’ (without the quotes)

In the services window scroll down the list until you come to Security Center (later on u can do the same for automatic updates too in the list).

Double Click on the Security Center option. The Security Center properties window will open. In the Start Type dialogue box it should read ‘Automatic’.

From the drop down menu select Disable. Click the Apply button followed by OK to Exit the Security Center Properties Window. Finally Exit Services msc.