Configure Windows 7 to Automatically Install Critical Updates
Automatic Updates will keep Windows 7 up-to-date with the most recent security patches. It is recommended to install new updates immediately.
STEP 1: Click on the Start button and then click on All Programs.
STEP 2: Click on Windows Update.
STEP 3: Click on Change Settings.
STEP 4: Under the "Important updates" section, select Install updates automatically (recommended).
Choose a convenient day and time for Windows to install updates, and then click OK.
If there are any important updates available from Microsoft, they will be downloaded and installed automatically.