It is very likely that the emergence of a new virus or Trojan could infect dozens, hundreds of computers, and possibly thousands. This is especially true for network worms. Therefore, it is essential that antivirus software providers are in a position to release updates for protection swiftly and efficiently to prevent these computer worms from becoming widespread.
Unfortunately, AV programs suffer from a number major problems which make them less effective. If you’re using any of these software it is important to be aware of these issues, so that you can take steps to protect yourself.
First most anti-virus programs are unable to detect all viruses and Trojans. This is a direct consequence of the fact that virus writers and hackers create new kinds of malware. Anti-virus software is not able to guarantee 100% security.
Another issue is that many common software issues can result in symptoms that resemble virus-related errors. It is crucial to check for other causes of problems before assuming that a computer has been infected by viruses. Some malware could display pornographic images on your screen, or news articles. Another sign is a screen that displays advertisements for websites that you haven’t visited.