Q: Why should I care about computer viruses? Isn’t it all just a bunch of hype drummed up by marketing departments for anti-virus software companies?
A: No, it is not! If you have not experienced a virus infection as of yet, consider yourself very lucky, especially if you have no Anti-Virus software installed on your computer. The virus threat is not going away. There are lots of people who just love to create havoc with their own virus creations as well as make it a profitable endeavor by obtaining your personal information.
Q: What is a computer virus?
A: A computer virus is a program, (malicious code) designed to spread itself by first infecting executable files or the system areas of hard and floppy disks and then making copies of itself. Viruses usually operate without the knowledge or desire of the computer user but many pose as a brand of anti-virus software themselves and attempt to obtain your credit card information by showing you false infections that it has found and claiming to be able to remove them once you purchase their full version. If you become infected, shutdown your computer as soon as possible and leave it off until a professional can remove the infection(s). The longer you run your computer while it is infected, the more it will be likely to become integrated, the harder it will become to remove and the less the success rate of having a functional operating system upon removal.
Q: What kind of files can spread viruses?
Since virus code must be executed to have any effect, files that the computer treats as pure data are safe. This includes graphics and sound files such as .gif, .jpg, .mp3, .wav, etc., as well as plain text in .txt files. For example, just viewing picture files won’t infect your computer with a virus. The virus code has to be in a form, such as an .exe program file, a .pdf file or a Word .doc file, that the computer will actually try to execute.
Q: How do viruses spread?
A: When you execute program code that’s infected by a virus, the virus code will also run and try to infect other programs, either on the same computer or on other computers connected to it over a network. The newly infected programs will try to infect yet more programs.
When you share a copy of an infected file with other computer users, running the file may also infect their computers; and files from those computers may spread the infection to yet more computers.
If your computer is infected with a boot sector virus, the virus tries to write copies of itself to the system areas of removable disks and hard disks. Then, the infected removable disks may infect other computers that read or boot from them and the virus copy on the hard disk will try to infect still more removable disks.
Some viruses, known as ‘multipartite’ viruses, can spread both by infecting files and by infecting the boot areas of removable disks.
Q: What do viruses do to computers?
A: Viruses are software programs and they can do the same things as any other programs running on a computer. The actual effect of any particular virus depends on how it was programmed by the person who wrote the virus.
Some viruses are deliberately designed to damage files or otherwise interfere with your computer’s operation, some try to transmit your personal information to a remote server while others don’t do anything but try to spread themselves around. But even the ones that just spread themselves are harmful since they damage files and may cause other problems in the process of spreading which will surely manifest in the form of slow operation, freezes, Blue Screens of Death (BSOD) or other undesirable outcomes.
Note: Viruses can’t do any damage to hardware: they won’t melt down your CPU, burn out your hard drive, cause your monitor to explode, etc. Email warnings about viruses that will physically destroy your computer are usually hoaxes, not legitimate virus warnings.
Q: What is a Trojan horse program?
A: A type of program that is often confused with viruses is a ‘Trojan horse’ program. This is not a virus but simply a program (often harmful) that pretends to be something else.
For example, you might download what you think is a new game but when you run it, it deletes files on your hard drive. Or, the third time you start the game, the program E-mails your saved passwords to another person.
Note: Simply downloading a file to your computer won’t activate a virus or Trojan horse; you have to execute the code in the file to trigger it. This could mean running a program file or opening a Word/Excel document in a program (such as Word or Excel) that can execute any macros in the document.
Q: What’s the deal with viruses and E-mail?
In order to activate a virus or Trojan horse program, your computer has to execute some type of code. This could be a program attached to an E-mail, a Word document you downloaded from the Internet or something received on a removable disk. There’s no special hazard in files attached to Usenet posts or E-mail messages; they’re no more dangerous than any other file.
Q: What can I do to reduce my chances of getting viruses from E-mail?
Treat any file attachments that may contain executable code as carefully as you would any other new files; save the attachment to disk and then check it with an up-to-date virus scanner before opening the file.
My personal feeling is that if an executable file shows up unexpectedly attached to an E-mail, you should delete it unless you can positively verify what it is, who it came from and why it was sent to you.
The recent outbreak of Facebook email viruses is a vivid demonstration of the need to be extremely careful when you receive E-mail with attached files or documents. Just because an E-mail appears to come from someone you trust does NOT mean the file is safe or that the supposed sender had anything to do with it.
It is often that I explain to my customers the importance of keeping their updates current and attempt to make the process of doing so easier for them. I know, I know… “I’m too busy to keep my computer up to date!” “When I get on my computer, I do so because I have things I need to do right then; I can’t take the time to update!” “I’m not sure if it is legit and I’m scared I’m going to install a virus!” I have literally heard it all. Well, not to worry. We will explore updates and why you should be sure that your entire system is current.
“But wait a minute! I thought you were going to talk about preventing viruses. What does this have to do with that?”
First of all, let me explain how upward of 90% of malware is being installed on and infecting systems every day in a way that is 100% avoidable.
Okay. So, now you’re infected with some malware. Knowing how you could have prevented it will help you greatly in the future; but for now, how do you get your computer clean?
Well, it can be a daunting task at times but if you’re willing to do some boring scans with a few basic and free tools, you can remove many viruses yourself.
First, you’ll need some of those aforementioned tools. There are many out there from which to choose but some will be found in any computer technician’s arsenal who is worth his or her salt. You should get a flash drive for downloading these tools on to so if you’re infected with malware that is blocking your internet access, you can run the programs you need from the USB drive.