Installing an anti-virus or a security software, after installing Windows is a must. This helps protect our Windows computer from viruses and other security threats. It is also important to keep your security software up to date at all times! Here are some very nice free antivirus software available for Windows 7 & Vista you might want to check out.

I have included only those antivirus programs which offer full real-time protection, and are not just stand-alone scanners!
1. Microsoft Security Essentials
Microsoft Security Essentials is Microsoft’s free antivirus offering to users of genuine Windows 7, Vista & XP users. It is specifically designed for individual consumer PC use using the smallest resource footprint possible to provide complete anti-malware protection and will include a new protection technology, as part of the Microsoft anti-malware engine, called Dynamic Signature Service (DSS).
Avira AntiVir offers you basic protection & protects your computer against dangerous viruses, worms, Trojans and costly dialers.
avast! Free Antivirus is perfect for people who send e-mails and surf popular websites. Its Anti virus and anti-spyware engine provides reliable protection against viruses, spyware, rootkits, trojans and other forms of malicious software.
AVG Anti-Virus Free lets you Surf & search with confidence, while LinkScanner, keeps you safe from select sites. AVG gives you online and offline protection from viruses, spyware, and other malware. Incidentally LinkScanner for some reasons is know to block several legit security help forums, for some reasons, best known to them. Our TWC Security Forum is also blocked by them. More on this here.
Apart from these freeware if you’d like to suggest any any more freeware antivirus software, do share below.
To see a list of consumer shareware anti-virus software that is compatible with Windows 7, visit Microsoft.
To see a list of business security software that is compatible with Windows 7, please visit the Windows 7 Compatibility Center.
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