This week I have started getting reports form Sysguy Clients (and in various tech maiing lists) that peope are getting an error when restarting their computers. The error reads that Windows Defender can not start. This is being caused because the beta version was installed as opposed to the released version. The Beta version of Defender expired Dec 31, 2006.
The remedy is fairly easy, uninstall Defender via the Control Panel Add Remove programs icon, then download and install the new version of Defender from Microsoft at http://www.microsoft.com/athome/security/spyware/software/default.mspx. This is a free downlaod and is bundled with 2 free support incidents from Microsoft. I have had success installing over top of the beta version but it is better to first remove then re install the new version. This ensures that files from the Beta are gone and properly replaced.