Windows OS is infected by a virus, worm, or Trojan horse if your computer displays one or more of these things:
* Screen shots of weird messages or pictures appear.
* You have less available memory than you expected.
* Music or sounds plays randomly.
* Files get corrupted.
* Programs are files don't work properly.
* Unknown files or programs randomly appear.
* System properties fluctuate.
Computer viruses, worms, and Trojan horses deliver their payload or instructions through three common ways.
1 - When an individual runs an infected program so if you download a lot of things you should always scan the files before executing, especially executable files.
2 - When an individual boots a computer with an infected drive, so that is why it's important to not leave removable media in your computer when you shut it down.
3 - When an unprotected computer connects to a network. Today, a very common way that people get a computer virus, worm, or Trojan horse is when they open up an infected file through an email attachment.
New ones come out by the numbers so that's why it's important to keep up to date with new ones that come out each day and there are literally thousands of malicious logic programs . Many websites keep track of this. There is no known method for providing 100% protection for any computer or computer network from computer viruses, worms, and Trojan horses, but people can take several precautions to significantly reduce their chances of being infected by one of those malicious programs. Whenever you start a computer you should have no removable media in the drives. This goes for CD, DVD, and floppy disks. When the computer starts up it tries to execute a boot sector on the drives and even if it's unsuccessful any given virus on the boot sector can infect the computer's hard disk. for any reason, such as when the hard disk fails and you are trying to reformat the drive make sure that the disk is not infected if you must start the computer using removable media.
By using good quality internet securities software is the best way to protect your computer from any of the above. Kept up to date with the most recent virus signatures Purchasing this from a reputable security company is recommended to ensure that your software. If you are not up to date an unrecognised virus will not be stopped by the software. A full security package will protect you from viruses, Worms, Trojan horses, keyloggers and will detect when a hacker is attempting to hack into your computer and prevent them from gaining access when you are online or connected to a network. It is not advisable to use a free antivirus service as these do not provide adequate protection and are a false economy. Recommended internet security software companies are:- Norton, McAfee and others.