Birusak arazoak sortu ditzaketen programak dira, ordenagailuan sartzeko bidea aurkitzen badute. Sartzeko modurik arruntenetako bat posta-mezuen bidez da.

Linux sistemak erabiltzen dituzten ordenagailuetarako birusak ez dira oso arruntak. Beraz, arraroa da birus bat jasotzea posta bidez edo beste moduren batean. Birus bat ezkutuan daraman mezu bat jasotzen baduzu, normalean ez du eraginik izango zure ordenagailuan. Hortaz, ziur aski ez duzu beharko birusen bila mezuak eskaneatzen dituen programarik.

You may, however, wish to scan your email for viruses in case you happen to forward a virus from one person to another. For example, if one of your friends has a Windows computer with a virus and sends you a virus-infected email, and you then forward that email to another friend with a Windows computer, then the second friend might get the virus too. You could install an anti-virus application to scan your emails to prevent this, but it’s unlikely to happen and most people using Windows and Mac OS have anti-virus software of their own anyway.