Norton email scanning message all over screen

Hello,
Every time i boot up my pc i keep getting scanning email 1 of 1 from symantec , which then fill my entire screen, i done a virus scan, which found some trojans and removed them, i also installed spybot s&d, malwarebytes and superanti spyware which all found trojans and malware which norton did not, but i still have the same probl;en with norton email scanning and sending it seems hundreds of emails to people i dont know, i contacted norton about this and they wanted $99 to fix it, why should i pay again? If anyone out there can help i would greatly appreciate it, i really dont want to have to reinstall windows xp .