How to perform windows update:
1. Click the START
button on you computer and select WINDOWS
UPDATE
* There is a possibility that you will get a windows asking to install a Microsoft tool that will enable the website to scan for updates on your computer, click YES. If you do not get the message that is ok.
2. When you visit the mentioned site the screen will look similar to this:

3. Click the link in the middle of the page labeled Scan for Updates
4. Your computer will now be scanned for any necessary updates. After it has finished scanning it will return a page similar to the following:

5. Click the link labeled Review and install updates located in the middle of the page
6. You will now get a screen similar to the following:

7. Click the Install Now button
8. You may receive a message similar to this: 
depending on which updates you need. Click OK, and follow the on screen instructions selecting all the default values. For example, click NEXT and OK for every step.
9. Once the current update is done, it will ask you to restart your computer, select OK to restart.
10. Follow these instruction from step one until you get the message that your computer is up to date and there are no available updates.