How to fight viruses, worms, trojans & bots
Keep checking your Apple computers on viruses, worms, bots and trojans. I had 5 email infections in 1 month, all via email (spam). Luckily my antivirus software (MacKeeper) runs a full virus check every month and identifies them easily. But antivirus software is simply not enough. An email worm can spread worldwide in just minutes. Fortunately, there are some easy steps you can take to help close that window of vulnerability and help keep email worms off your system.
Rule 1: Identification - Understanding the nature of the attachment is the first step towards email safety. Any executable type attachment has the potential to be infected. This covers a wide range of extensions. Complicating matters is that, by default, Windows suppresses file extensions. Make sure you have file extension viewing enabled. On Apple computers file extension viewing is standard enabled.
Rule 2: Intent - An executable type attachment should not be opened unless it was specifically requested or expected. Since email worms are sent to addresses found on infected users' machines, just knowing the sender is no proof of intent - they may well be infected. In fact, odds are an email worm will arrive from someone you know and the sender is oblivious to the viral email being sent from their machine. Worse, today's worms spoof the From address, so it may well be that it's not even from the person you think it is.
Rule 3: Necessity - This is the simplest rule to follow, but one that many people ignore. If you do not need the attachment, don't open it. Delete the email instead.
Rule 4: Update your Apple software - If Apple releases an update for your operating system do implement it. And remember - as in aviation, security is never passive. It's an ongoing process and new vulnerabilities are constantly discovered.
Stay awake and vigilant. And ... do make backups!
(Source: TRApple.nl | Serge)