How do I prevent unwanted tabs (scam & sales ads) from opening, both at start-up and when perusing the web? I'm using FF 3.6.8. This problem began around July 2010. My homepage loads just fine, but a second tab loads as well (which isn't in my homepage preferences). The "registry defender" ad/scam is particularly annoying. I've blocked all cookies except for certain sites, but that didn't help. Pop-ups are also blocked. I've repeatedly run SuperAntiSpyware and Malwarebytes but neither program has fixed the problem. Any advice would be appreciated!