On the Privacy tab, under Pop-up Blocker, select or clear the Turn on Pop-up Blocker check box, and then click OK.
If you select Turn on Pop-up Blocker, your pop-up blocker is now on you can add exception by clicking Settings and typing the web address of the site you would like to allow pop ups from.
If you deselect Turn on Pop-up Blocker, you pop-up blocker is off