|If you're currently using Internet Explorer, using Firefox instead should help. |
You also need to have first-class antispyware/antivirus & firewall package installed. That means not relying on any of the free ones. they just aren't good enough against todays malware-infested internet.
Norton Internet Security takes some beating because it offers rock-solid, all-round protection and, unlike the competition, it doesn't slow Windows down.
I've never been infected or had my browser hijacked since I started using Norton 4 years ago.