This is clearly off-topic for the web design forum. So I will be locking this thread.
But if you have no antivirus and you think you need one (that's a VERY good thought), then why not install one?
AVG, Avast, Avira and even Windows Security Essentials are free. Also there are good paid ones (like Kaspersky, Norton, McAfee). And they all have companion 'Internet Security suites' that protect you against more than just viruses.
Kees

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