First scan with Microsoft Security Essentials - Microsoft Security Essentials test drive
I suggest you run a full scan first time then use the Quick Scan option. Microsoft Security Essentials allows you to customise when scans are run. The default is once a week on Sunday 2am. I recommend you scan at least once a day. It also lets you tweak how much computer power it uses running anti-malware checks. The default seems to work okay.
Microsoft Security Essentials is designed to provide home users with basic anti-malware software. It is supported by the Microsoft Malware Protection Center, which updates AV signature files every four hours. It also provides a heuristics function, which analyses malware-like behaviour and sends information back to the Microsoft Security Response Center for further analysis.
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