While we are covering all of the free anti-spyware applications, it’s only fair to talk about the completely free Windows Defender tool built into Windows Vista and available as a free download from Microsoft for XP users.

This application lets you do manual, scheduled, and real-time scanning with automatic updates of spyware signatures, without a large performance penalty. You can also use it to control what applications run at startup.

Of course, if you are already using a third-party anti-spyware application, there’s really no reason to have Windows Defender’s real-time scan enabled. In this scenario you can get a performance increase by disabling it, and that’s not a Windows Tweaking Myth. If you aren’t sure, you can always ask a geek.

Using Windows Defender

Selecting Tools and Settings will start you off in the right place to stop applications from running on startup by selecting Software Explorer. We can make other adjustments from here as well.

If you find the Real-Time scanning annoying because the hard drive is always busy, just go into Options and disable it.  Uncheck the box for “use real-time protection”. This can be especially helpful on a laptop, where every little bit of tweaking helps battery life.


If you have automatic updates set you won’t need to worry about updating the protection database.

Windows Defender actually allows us several options for scans. Quick Scans which scan essential OS directories, Full Scan which scans all files and folder, and Custom Scan which allows us to choose what to scan.


Windows Defender has come a long way since its inception. It is really a solid anti-malware application and has tons of features including scheduling scan times, viewing scan logs, and controlling its behavior.

If you are on XP and have not installed it yet then I would recommend using a third party utility.  There are other tweaks we can utilize as well.  For instance check out The Geek’s article on how to stop the annoying “Windows Has Blocked Some Startup Programs” balloon.

Download Windows Defender For XP and Server 2003

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