1. Visit Windows Update: Make sure that you have all the Critical Updates recommended for your operating system and Internet Explorer. This includes SP1, SP2 and Sp3 if you use Windows XP. The first defense against infection is a properly patched Operating System. 
    • Windows Update: Windows Update
    • If you have Word, Excel, Outlook or other Office programs installed. Consider using Microsoft Update instead of Windows Update. See the FAQ page here for more information: Microsoft Update 
  2. Also, download and install Microsoft Baseline Analyzer. (Note that MBSA is only for Win 2000 SP3 or later and Office XP or later) When run, it will check system for security exposures, including missing updates. I suggest running it weekly. You can obtain more information here: MS Baseline Analyzer
  3. Adjust your security settings for ActiveX: Select Internet Options from the Control Panels, or from Internet Explorer (Tools -> Internet Options) Press ‘default level’, then OK Now press “Custom Level.” 
    • In the ActiveX controls and plug-ins section set these options: ‘Download signed ActiveX controls’ – Prompt ‘Download unsigned ActiveX controls’ – Disable ‘Initialize and script ActiveX controls not maked as safe’- Disable All other options accept the default 
  4. For Windows XP SP2+ users, check this link for additional steps you can take to secure Internet More >