I spoke to a colleague about it and he asked my why I didn't just use windows defender. I said that it was not good enough and he asked why. These were the days before most people started using it. His argument was that Windows Defender was not advertised at all, nobody paid an army of bloggers to defend it an big it up but that did not make it an inferior product. Why would Microsoft make an anti-virus any less effective than a paid anti virus? I really had no decent argument against it. I guess we just feel better about something if we pay for it. Been using Defender ever since and never had a problem. At least my antivirus doesn't automatically turn off when my credit card expires and they can't bill me.