I used Norton for several years. Switched to AVG because of Norton's high maintenance costs, high resource usage, and general problems installing/uninstalling, etc. I started with AVG free & quickly upgraded to Pro. The Pro version offers a one time fee (less than NAV) for a 2 year license on 2 machines including all program and definition updates. It allows much more user control over scheduling, which files and extensions to scan, control of the virus vault, email scanner, etc. I have been very happy with it.
That being said, no anti-virus program is perfect. Even with heuristics and diligent updating, someone has to be the first victim in the wild before the virus can be analyzed and a definition issued. Further, anti virus protection is only one part of the security equation. I also use Zone Alarm Pro, BoClean 4.11 (anti-trojan), strong WPA encryption on my wireless network, a random password generator for online banking and other important activities plus Spybot, AdAware and Pest Patrol. Finally, I usually reformat and reinstall the OS and all software about once a year.
If all this seems like a lot of work, well maybe it is but I enjoy such things and have not, to my knowledge, been infected in the last 4 1/2 years.
Such are the times we live in. Hope my somewhat off topic rambling has been of some help.
I used AVG free edition for over two years and always kept it updated. No problems. Then a couple of weeks ago my one computer was infected with the Opas Worm (probably through my own carelessness). I tried everything with AVG and could not remove it. So I went to Norton and Norton took care of business. Here's my question: On my one computer AVG scans 27,000 files on a complete scan, Norton scans 38,000. On the other computer AVG scans 47,000 and Norton scans 84,000. Big difference. Isn't it possible that some of those files that AVG is not even scanning could be infected and you'd never know it? Thanks.

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