04-05-2011 08:09 AM
Welcome to the Norton Community Forum
Windows Defender has a real time component to it that would interfere with NIS 2011. If you disable the real time component, then it could be used as an on demand scanner. It is not the one that is usually recommended in the Forum though. We usually recommend the free versions of Malwarebytes and the free version of SUPERAntiSpyware as on demand scanners. They will not interfere with your Norton products. Thanks.
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