Microsoft have released a number of patches to fix recently reported vulnerabilities within Windows, Office and Internet Explorer. These vulnerabilities may allow an attacker to gain control of your computer or cause it to crash.

More information about what has been patched is available from Microsoft's 10th October Security Bulletin here: http://www.microsoft.com/technet/security/bulletin/ms10-oct.mspx

If you don't have automatic updates enabled, install the updates by visiting https://www.update.microsoft.com

I highly recommend that you enable automatic updating - to find out how, visit http://windows.microsoft.com/en-us/windows7/Updating-your-computer