I found a cure for the URL MAL BLOCKED SITES that kept popping up. I used Malware bytes along with numerous other programs to no avail until I used TDSSKILLER. It is a free down load and I haven’t had a problem since. Here is the link. http://www.softpedia.com/get/Antivirus/TDSSKiller.shtml
Sorry but this isn’t a one size fits all situation, the URL:MAL alerts can be for several different types/variants of infection.
That is why it is recommended that these should be investigated by a malware removal specialist and the information is contained here http://forum.avast.com/index.php?topic=53253.0.
This way people aren’t alone, get qualified help and are given guidance when running tools that could potentially harm their system.