Best Free Anti-Virus Software Updated May 3, 2006
There are two equal recommendations in this category. First there is AVG Antivirus 7.0 Free Edition. This product [1] has been continuously refined since it was first released in 1991 and now offers solid protection capabilities. Additionally, it's relatively small, light on resources, has regular automatic updates and handles email scanning. There is a free and a pro version, the only difference being that the free version has a few non-critical features disabled and has no direct technical support.
Equally effective is the free Avast! scanner [2] though its funky media player style interface is not to everyone's taste. Avast! also required periodic re-registration while AVG does not. However Avast! does not seem to suffer the signature file update problems that plague some AVG users.
Both AVG and Avast! are excellent free products that will meet the needs of most users. However neither of these products though can be considered to be the best in their class. That title belongs to commercial products like NOD32, Kaspersky AV and others. They are however capable packages and offers the financially challenged a real alternative to the major anti-virus suites.
However if you use these free products in conjunction with a free on-demand scanner, you can achieve a level of detection approaching that of the best commercial products. Further improvement is possible by creating a layered defense using additional free security products such as Ewido.
On-demand scans should be run regularly, at least weekly, to check for viruses that may have been missed by your main scanner. My top recommendation as on on-demand scanner is AntiVir Personal Edition Classic [3]. It offers somewhat better detection rates than either AVG or Avast! but the lack of email scanning precludes recommendation as a primary scanner. However as an on-demand scanner, it's first rate. If you use it in this role, make sure you disable its resident virus guard during installation to prevent it interfering with your main AV scanner. Note that the recently released V7 unfortunately introduces a time limited license though apparently this will be renewable.
Another good option for on-demand scanning is the free version of the commercial AV product BitDefender [4]. It's a first class product with outstanding detection rates but as the free version lacks an email scanner and a resident virus guard, it's only really suited for use as an on-demand scanner rather than your main AV product. There are some other limitations as well. First it has an annoying habit of detecting malware products that have been quarantined by other security products and you can't exclude these areas from subsequent scans. Second it is only available on a one year non-renewable license.
[1]
http://free.grisoft.com/freeweb.php/doc/2/ (16.0MB)
[2]
http://www.avast.com/eng/avast_4_home.html (8.8MB)
[3]
http://www.free-av.com (8.7MB)
[4]
http://www.bitdefender.com/PRODUCT-14-en--BitDefender-8-Free-Edition.html (13.2MB)