There is no single silver bullet that can protect a computer from all malware. However, there are a number of steps that can be taken to greatly reduce the risk of infection. First, always keep your operating system and all software up to date with the latest security patches. Second, use a reputable antivirus program and scan your computer regularly. Third, be cautious when opening email attachments or clicking on links, even if they appear to come from a trusted source. Finally, install and use a firewall to help block unauthorized access to your computer.