McAfee Total Protection
Norton Internet Security
AVG Free Anti-Virus (Free)
avast! antivirus Home Edition (Free)
Avira AntiVir Personal (Free)
GuildPortal does not display advertisements, in any form whatsoever, on subscriber guild web sites. Additionally, when advertisements are displayed on non-subscriber sites, they are never of the pop-up, pop-under, or link hijacking type. We stick to straight text and banners only, and in designated areas of the page.
Some software is installed, often without your knowledge, when you install other software, that can cause advertisements to show on web pages you visit. Sometimes, the advertisements take the form of pop-up/pop-under windows. Other times, they will actually hijack text on web pages, matching keywords found on the pages you visit to advertisements, injecting links.
The sneakier ones won't do it on every page, nor on every site, that you visit. They do that so that you are less likely to suspect your system.
GuildPortal recommends that you first -- and foremost -- run a browser that is neither IE6 or IE7 when browsing the web, or that you keep it patched up to the very latest version using Windows Update. This browser has a long history of allowing web sites to actually load and run executables on your computer without your knowledge or consent. Speaking strictly for GuildPortal, we use Google Chrome almost exclusively on our Windows machines, except for when we need to do compatibility testing.
Next, we recommend that you install, and keep up-to-date, good anti-virus and anti-spyware/adware software.
Some of the anti-virus products on the market do not detect some of the trojans/viruses that are fairly common. For example, Norton does not detect the Gamevance software, while McAfee does, identifying it as a trojan.