Just like the other versions of Windows operating system, Windows 7 also needs the installation of some best antivirus software so that worms, viruses, Trojan horses and malwares can be easily detected for the efficient working of operating system. There is lots of freeware antivirus software that are available nowadays. Some of the most famous and best free antivirus software’s list for Windows 7 operating system is following:
1-Microsoft Security Essentials anti-virus solution:
Microsoft Security Essentials anti-virus solution was first designed for Windows vista but now it is also working well for the Windows 7 operating system. The amazing thing about this antivirus is that it does not affect the processing speed of the system.
McAfee VirusScan Plus is one of the best options for securing the any version of windows operating system from the malicious things. It performs a very effective operation against the spyware and adware. Another important feature of this antivirus is its ability to secure the system from malicious websites.
3- AVG Anti-Virus Free Edition:
AVG Anti-Virus Free Edition is one of the most famous free antivirus software that can be seen nowadays. This software is not only suitable for Windows 7 but also for all other versions of Windows. It also provides the many other features like Windows recommendations and protection against Spyware. 
4- Avira Antivirus Personal Edition:
Another amazing free antivirus software is Avira Antivirus Personal Edition. It is considered as one of the fastest antivirus software in terms of finding or detecting the unwanted objected. This software is so much common that it can be obtained easily from the internet.
Norton Antivirus 2010 is more effective than its previous versions. This new version of Norton is considered as one of the best antivirus software for all versions of windows including Windows 7.
Avast! Antivirus Home is the most favourite free antivirus software of millions of users in all over the world. People really love to use this antivirus due to its remarkable features. It’s a complete antivirus package for those who want to protect their computers from all kinds of malicious objects and harmful websites. 
Like Avast, Kaspersky Anti-Virus 2011 is another famous antivirus that is really used on a large scale because it does not affect the speed of system and works amazingly for detecting and removing the unwanted objects.
Panda Cloud Antivirus is free antivirus software that provides the fastest accessibility towards the all malicious things. Lots of additional features have also introduced in the new version of this software like more effective scheduling. 
9- ZoneAlarm Extreme Security:
ZoneAlarm Extreme Security has lots of additional and unique features like the encryption of data along with the strong resistance against unwanted objects. 
10- F-Secure Internet Security Suite:
F-Secure Internet Security Suite is a combination of lots of features like protection against virus, worms and back-up of hailed data.
If you have any computer related problem, you can ask it at our Question & Answer portal and our experts will answer your queries.
When I installed antivirus other than Microsoft Security Essentials, I found that my Windows 7 PC crashed a lot. It was definitely the antivirus causing the crashes since they stopped when I uninstalled them and replaced them with MSE.
You made some good recommendations here. Free trials are the best way to be sure the antivirus protection is effective and that the software does not slow down your computer.
Microsoft Security Essentials is the best of them and I think you can use it ,leaving aside your paid antiviruses too
Am using Microsoft security essentials and found very useful with windows 7 as well as windows xp, now am using combined Bit defender and Microsoft security essential. its very good combination i would say.
Microsoft Essentials is one of the best free antivirus available for Windows 7 and it works like charm.
Bitdefender always leading the list
ZenOK Free Antivirus is one of the best free antivirus available for Windows 7 and it works like charm.
I must say that is BIG difference between free and paid Antivirus. From our research Bitdefender antivirus pro 2011 is top Antivirus and free version is very low quality…. Cheers!
I always appreciate for those who understand that actually what are the major different between one antivirus with another antiviruses. But can anybody share me more and more.
I have been surprised that all websites are agree with that: MSE is number one free security tool. This is a great tool but I think Avast Free edition is not worse
Antivirus Reviews recently posted..Webroot Antivirus with Spy Sweeper
I thought E-scan should be there
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