In addition to Avast, you should also get Malware Bytes Anti-Malware. Updates are required to be run each time the free version is used. I have the free version, it is good. If you want full-time protection from MBAM, you can purchase a $25 USA dollars license key, which might help just in case Avast misses something. Avast hasn’t missed anything, so right now, I just have Avast and the free version of MBAM. Works very well. You can get the program at www.malwarebytes.org

Note however, that your first line of defense is ALWAYS an up-to-date Anti-Virus Program. Optional malware removal catches what your Anti-Virus might miss. I always manually update Avast defitions, than do a full scan, than update MBAM and do a full scan, when I want to check for malware.

Jack