Originally Posted by jayeff

To make it less aggravating for your visitors and to make it seem less like you are hijacking them yourself, you could simply direct those with Zango's toolbar (or any like it) to an alternate main page.

Since these visitors are likely to be hijacked anyway, it would not be any great real loss to use (some of) your usual promo space on such pages to warn against scumware and provide links to sites (or set up your own page) offering info on how to remove it.