12 ways how to know if your computer has a virus [Guide]

computer virus safeYou have probably heard of people’s computers getting infected with viruses or malware.  You may have even had this happen to your own computer.  Just like with a person, a virus infects software on your computer and causes it to malfunction.  Malware is another type of malignant software that can infect your computer.  In order to protect your computer from these attacks, the first step is to understand exactly what a virus or malware program is and what damage they can cause.  Sometimes the effects are so subtle that you don’t even realize immediately that your computer has been infected.

Have you ever been bothered by poor performance on your computer, such as running slowly, not responding to your commands or finding unknown software that you don’t remember downloading or installing?  You end up puzzled, scratching your head and wondering why the newly purchased computer is already performing at a subpar level.  You might begin to panic, but you don’t have to worry about it. You don’t need to call the computer geeks or bring your computer all the way to the after service center. These problems can be solved by you. Even if you have an “antique” computer, there are ways to make it fly again.


These symptoms might seem intimidating, and you might have kept asking yourself, “What have I done wrong?!” You tend to surf the internet carefully and you don’t recall downloading any strange or unknown files.  How did your computer get infected?  Before we look at signs that might indicate an infection, let’s look at how computers commonly get infected.

A virus is like a parasite: the internet is the host.  Having contact with the internet means that, just like a flea, a virus or malware software program has the chance to “jump” from the internet into your hard drive.  Today, anyone can browse information on the Internet or establish their own web pages. Hackers have developed viruses or malware and disguised them as free tools on various websites that people download.  An example could be a search engine toolbar tool or something that claims to track your favorite websites.  You might think that this is a useful tool and download it only to discover later that there was hidden virus or malware code within that tool that has now spread to your computer.

Another type of virus or malware is coded into the website itself; when you visit the site it will try to automatically run a malicious script, modify your system registry entries, steal your user information, or install malicious programs within your computer.  You can avoid these types of attacks by always using official and secure websites.

One more way that hackers try to infect computers with viruses or steal information is by using a network.  Computers that are connected via a LAN (local area network) can freely access the files stored on the hard drives of the other computers in the LAN.  Thus, if a hacker manages to get the virus or malware onto just one computer in the LAN, all of the other computers (and the data stored on them) are potentially at risk.

Email is another type of transmission system for viruses and malware.  They have the ability to access your email address books and send out mass messages to everyone in your address book disguised as an email from you.  If someone opens the email and downloads the attachment, the virus will infect their computer as well.  Viruses may also take important information from your hard drive and email it to the hacker or other random people.  Hackers may also send spam email to “fish” for your personal information: they will pretend to be a representative of a credit card company or some other company where you have an account and claim that they need you to verify your username and password for security purposes.  Once you send them the information, your identity has been stolen.

A final mode of virus transmission is via mobile storage mediums such as usb drives and portable hard drives.  If you have an infected file on your computer, it may save itself to a portable storage device.  Then, it will copy itself onto the hard drive of the next computer that you access with that device.


Now that you are familiar with various ways that a computer can be infected by a virus or malware, let’s move on to the diagnostic process. If you have ever noticed the following symptoms, your PC is most likely (over 90%) already infected by a virus:

  • Some strange information and images show up on the screen
  • The CD-ROM tray pops out without any reason
  • Some program automatically runs
  • A program attempts to access the Internet without your authorization
  • Friends or acquaintances tell you that they received your message but you never sent an E-mail
  • There are tons of “No Subject” or “No Address” emails in your inbox
  • Your operating system frequently freezes or crashes
  • You cannot start your computer or operating system
  • Software is running slower than a turtle
  • Files and Folders are lost or contents are modified without your authorization
  • The hard drive is frequently being accessed (the LED indicator light for the hard drive is blinking crazy fast)
  • You either cannot open IE or it opens itself randomly without your authorization

If you notice any of these symptoms, the likely culprit is some virus or malware that has infected your computer.


It is important not to panic if you realize that your computer has a virus.  There are many ways of cleaning and removing viruses and malware programs from your computer.   In addition, there are several important steps you can take to protect your computer from ever getting infected in the first place.  If you would like to protect your computer or find out how to scan for and remove viruses, visit those specific articles listed here on dotTech for all the information you need. We will be writing many more how-to remove viruses articles in the near future. Stay tuned!

Related Posts