Avast is an excellent free antivirus. First I suggest you update to the newest version (4.8) and use the boot-time scan of 4.8 and quarantine anything it finds.
After that scan with Superantispyware free, Malwarebytes Antimalware free, F-secure Blacklight and the Kaspersky AVP Tool.
To keep your computer clean from malware, I suggest you stick with Avast. Occasionally scan with Superantispyware free and Malwarebytes Antimalware free, you can also scan with Spybot (and turn on the Immunization function).
For browsing, you should use Firefox (with the Adblock Plus addon) or Opera instead of Internet Explorer or Safari - this reduces the chance of malware getting on your computer.
AVP Tool: http://devbuilds.kaspersky-labs.com/devbuilds/AVPTool/
· 1 decade ago