How does a computer get infected with a virus or spyware?

There are literally dozens of different ways a computer can become infected with spyware, viruses, and other malware. The following document contains is a list a number of these infection methods; listed in the order we believe to be most to least common.

Accepting without reading

By far one of the most common ways a computer becomes infected is when a user accepts what they see on the screen without reading the prompt before proceeding. For instance:

1. While browsing the Internet, an Internet advertisement or window appears that says your computer is infected or that a unique plug-in is required. Without fully understanding what it is you're getting, you accept the prompt.
2. When installing or updating a program, you're prompted (often checkboxes already checked) if it's okay to install additional programs that you may not want or are designed to monitor your usage of the program.

Opening e-mail attachments

Computers can become infected when users open e-mail attachments that contain malicious code. Even if the message is from a co-worker, friend, or family member, always use caution before opening a link or downloading an attachment. As a general rule, do not open e-mail you were not expecting to receive.

Not running the latest updates

Many of the updates, especially those associated with Microsoft Windows, are security oriented. Always keep your operating system and programs up to date. The plug-ins associated with your browser can also contain security vulnerabilities. To make sure you have the latest versions, run the Computer Hope tool for checking installed plug-ins and their versions.

• How to update a Microsoft Windows computer.

Pirating software, music, or movies

If you or someone on your computer is participating in a bit torrent program or some other unlawful exchange of copyrighted music, movies, or software, you may be at risk. Sometimes these files and programs contain viruses, spyware or malicious software in addition to what you believe your are downloading.

No antivirus spyware scanner

If you're running a computer with Microsoft Windows, we highly recommended you have some form of antivirus and spyware protection. This software removes existing (if any) viruses and helps prevent future infections.

Downloading any infected software

When acquiring any software (programs, utilities, games, updates, demos, etc.) via the Internet, make sure you're downloading the from a reliable source. Be sure to run your downloads through your antivirus and spyware scanners upon completion. As we stated in a previous section, during the installation process, reading all prompts about what the program is putting on your computer.