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Dear, You can use "Quick heal total security" This Antivirus having a good in result.

Windows 8 has its own antivirus built in.
Windows 8 includes an automatically loaded updated version of Windows Defender
which is a full antivirus based on Microsoft Security Essentials.
(Windows Defender
for XP, Vista, and Windows 7 was only antispyware.)
So if you upgrade the protection
is automatic and is on by default at installation.

Windows Defender and Windows SmartScreen fight viruses and other malware
http://windows.microsoft.com/en-US/windows-8/windows-defender#1TC=t1

How to Create a "Windows Defender" Shortcut in Windows 8
http://www.eightforums.com/tutorials/6862-windows-defender-create-shortcut-windows-8-a.html

How to Add a "Windows Defender" Cascading Desktop Context Menu in Windows 8
http://www.eightforums.com/tutorials/8450-windows-defender-cascading-desktop-context-menu-create-windows-8-a.html