It’s not always easy to tell if your computer has been compromised. More than ever before, the authors of viruses, worms, Trojans and spyware are going to great lengths to hide their code and conceal what their programs are doing on an infected computer.
It’s very difficult to provide a list of characteristic symptoms of a compromised computer because the same symptoms can also be caused by hardware and/or software problems. Here are just a few examples:
- Your computer behaves strangely, i.e. in a way that you haven’t seen before.
- You see unexpected messages or images.
- You hear unexpected sounds, played at random.
- Programs start unexpectedly.
- Your personal firewall tells you that an application has tried to connect to the Internet (and it’s not a program that you ran).
