After this week's first instance, online security experts told Internetnews.com to expect more attempts to use ad servers as a means to distribute Bofra/Iframe exploits, which can cause viewers computers to download software allowing others to control it remotely. One expert even recommended sites and viewers disable banner ads until fixes can be developed. Another recommended people not click on ads - a requirement for infection. Windows users that don't have XP Service Pack 2 will remain vulnerable so long as they use Microsoft's Internet Explorer browser. Users of other operating systems and browsers should be free from trouble.