Why does google sites go to advertisement sites?

I go to google trying to find a site. When I click a site it tries to load the page but then goes straight to an adverising page. Why does it do this? How can I stop it?

Trish2011-01-24T15:51:43Z

Favorite Answer

You have the Google redirect virus.

Bleeping computer has the best advice for redirect virus.

Go to the link, scroll down to "Automated Removal Instructions for the TDSS, Alureon, or TDL3 Rootkit using TDSSKiller"

Follow the instructions very carefully.
Source(s):
http://www.bleepingcomputer.com/virus-re…

Marvin2011-01-24T23:25:15Z

You have a google redirect virus.
Many antivirus apps have problems detecting this kind of virus because it is a "rootkit" virus.

You should download and run hitmanpro and clean it up.
hitmanpro is free for the first 30 days.
http://www.surfright.nl/en/hitmanpro