Laptop has a virus after cleaning it a couple days earlier help?

I have used my anti-virus Webroot to delete a trojan virus that was giving me false pop-ups saying my laptop is at risk of virus alerts and etc. So I used Webroot to scan & delete the virus. I had taken it to Best Buy's Geek Squad the day before and they said that Webroot had cleaned the virus off the computer. Now today I was checking my emails and then I went back to Yahoo's homepage then Webroot informed me that it auto-quarantined a Troj/VB-FAQ. Now I'm getting the same fake Antivirus alerts and my internet is opening by itself. When Webroot informed me of the auto-quarantined virus I started a scan. The Geek Squad agent at Best Buy had told me that when I came in contact with the virus yesterday and performed the scan that the virus was taken care of and was gone after he restarted the laptop. Now today I'm getting the same symptoms, but Webroot has auto quarantined the Troj/VB-FAQ. How is it that I can continuously getting these viruses when I'm not going onto virus filled sites?