How to: Disable Windows Defender in Vista

Vista - the 11' deep end of the pool

I just took the plunge on my laptop and installed Windows Vista Business Edition...I figured that if some of the doctors that I support (I work at an Orthopedic clinic & surgery center) are buying computers with Vista, then I should probably know what they are talking about when they ask me questions...

First thing's first, protect that computer

As part of my installation process, I wanted to configure my usual combo of Antivirus and Antispyware (i.e. Avast! and Spyware Terminator, respectively).

No problem installing Avast! - the download from Alwil's website worked like a charm, and did not complain in the slightest when I installed it.

Defender really wants to protect my computer

Now, for the Antispyware. Interestingly (but not surprisingly), I realized that Windows Defender is pretty well hooked into the operating system, evoking memories of the whole IE debacle back early in 2000.

Disabling Windows Defender

I've discovered that there are a few places that you need to go in order to disable Windows Defender so you can install your own antispyware software.

First, open up Windows Defender, click on 'Tools'> 'Options'.

Uncheck 'Automatically scan my computer (recommended)'.

Scroll down a bit...

Uncheck 'Use real-time protection (recommended).

For good measure, scroll down a little bit more and find 'Administrator options', and uncheck 'Use Windows Defender'.

Close out of Windows Defender.

Ok, now that you've disabled Windows Defender, you will get an error from the Microsoft Security Center stating that your antispyware software is turned off.

Click the alert balloon (as pictured above), or click 'Start'> 'Control Panel'> 'Security'> 'Security Center' and click 'Malware protection', click the button under 'Virus protection or Spyware and other malware protection' and choose 'Show me my available options'.

When the 'Choose an antispyware option' window appears, click 'I have an antispyware program that I'll monitor myself'.

One thing I noticed was that Spyware Terminator does not report its status to the Security Center, so it isn't monitored (and you won't receive Security Center alerts regarding Spyware Terminator).

Explanation from Microsoft:

Windows does not detect all antivirus and antispyware software. If you are sure that you have anti-malware software installed, it is turned on, and it is up to date, you can click I have an antivirus program that I'll monitor myself or I have an antisypware program that I'll monitor myself to stop receiving notifications from Security Center about your anti-malware software. If you do this, Windows will not monitor your anti-malware software status or alert you if it is off.

So, it is up to the software publisher to write code that will tell the Security Center how to monitor their software.

One final note to keep in mind. If the computer is part of a domain structure (i.e. a corporate or business environment), you may find that the domain administrator is controlling the Security Center behavior via Group Policies.