Antivirus programs, by their nature, introduce a degree of risk. Since they have to scan malicious data to stop attacks (and thus need extensive permissions), a piece of malware that exploits antivirus flaws can typically run with impunity. That could be much more difficult if you're using Windows 10's built-in safeguards, though. Microsoft is gradually rolling out a Windows Insider preview where Defender Antivirus has the option of running in a sandbox -- the first "complete" solution to do this, the company said. Should the worst happen and malware targets Defender Antivirus, any hostile actions will be limited to the antivirus tool's environment instead of running amok on your PC.