ERROR # 0x6a4-0xf9fx3999 popup is a browser-based scam that uses social engineering to deceive users into believing that the PC has been infected with a Storm Worm and Riskware. This popup informs the user not to ignore this message, but to immediately call technical support to prevent further damage. Scammers use the “ERROR # 0x6a4-0xf9fx3999”