Hi ye all,
To prevent virus infection on your machine there is a collective avoidance method, also known as
digital hygiene 
.
General RulesGarbage In, Garbage OutIf you allow infected software onto your machine, viruses can generate.
More Connections More InfectionsThe more ways the interface of your machine connect to others, the more ways open for viruses to land on your machine.
Piracy Has Its PriceInfections from store-bought software or Cd's are rare.
Illegal source shared software means a higher chance of infections
Use BackupsRegular back-ups of your system is useful as a "last ditch defense".
Control Access to Your PC.
Use a boot password, but do not loose it or you are in serious
trouble.
That's it folks,
polonus