ClamWin
ClamWin is a free antivirus program that support Microsoft Windows 98/ME/2000/XP/2003/Vista.
Features:
- High detection rates for viruses and spyware;
- Scanning Scheduler;
- Automatic downloads of regularly updated Virus Database.
- Standalone virus scanner and right-click menu integration to Microsoft Windows Explorer;
- Addin to Microsoft Outlook to remove virus-infected attachments automatically.
But this software does not provides on access scanning, user need to manually scan system. But i like this, because it can save some resources for better performance on low level pc.
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