No, updating to Firefox 5.0 won't affect the McAfee security program, beyond their Site Advisor extension for Firefox. The Site Advisor extension is blocklisted by Mozilla due to the Site Advisor extension being the #2 cause of crashing the Firefox 5.0 betas. McAfee was notified of the problem long before that extension was added to the blocklist. Now it is up to them to fix it. <br /> https://addons.mozilla.org/en-US/firefox/blocked/ I have read that McAfee is working on a re-written version that is projected to be available in the 3rd week of July. By then, Firefox 6.0 will probably be released. I hope they are smart enough to have that extension compatible with 6.0, or they'll be putting their users through unnecessary aggravation all over again.