Whenever a new version of Windows comes out, I usually avoid buying from that first batch, since there always seems to be glitches to work out. It appears that Windows 7 is no exception since it was shown to be vulnerable to 8 of the 10 “freshest” viruses circulating around the internet. SophosLabs used a copy of Windows 7 on a clean machine that was configured to follow system defaults without loading any anti-virus software. Of the 10 viruses that they introduced to the machine, 2 would not operate correctly under the newest version of Windows
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8 reasons why you should use anti-virus software with Windows 7