Many personal computers are now connected to the Internet and to local area networks, facilitating the spread of malicious code. Today’s computer viruses may also take advantage of network services such as the World Wide Web, e-mail, and file sharing systems to spread, blurring the line between viruses and worms.
An e-mail virus travels as an attachment to e-mail messages, and usually replicates itself by automatically mailing itself to dozens of people in the victim’s e-mail address book.
Following are the Symptoms of a computer virus
*The computer restarts on its own
*The computer runs slower than usual
*Disks or disk drives are inaccessible
*Applications on the computer do not work correctly and You see unusual error messages
*The computer stops responding, or it locks up frequently
*The computer crashes, and then it restarts every few minutes
You can protect your computer against viruses with a few simple steps:
Be Sure Firewall is Activated
*If you are truly worried about traditional (as opposed to e-mail) viruses, you should be running a more secure operating system like UNIX. You never hear about viruses on these operating systems because the security features keep viruses (and unwanted human visitors) away from your hard disk.
Use Updated Antivirus Software on the Computer
*If you simply avoid programs from unknown sources (Internet downloads), and instead stick with commercial software purchased on CDs, you eliminate almost all of the risk from traditional viruses.
*Do not open an e-mail attachment unless you know who sent it. Even then, it’s not totally safe, as a sneaky virus that has infected a friend’s computer can access the e-mail address book, send a message to everyone, and attach itself. To be completely safe, scan the attachment with your anti-virus software before you open it.
Keep Operating System Up-to-Date
*Regularly back up your files. Should your system become infected, so you won’t lose valuable data.