Signs that my computer is being infected with a virus

This article was modified on 2012-08-28 07:35:37

My computer seems to work hard. It seems to be more noisy as it seems to use more CPU and I suspect that it might be infected with a virus. How do you tell if it`s a virus or anything else ? After what should I look ?

Before suspecting a malware infection did you checked if it`s because of the dust ? My laptop also became noisy but it`s already several years old...If this is not the case did you recently installed an application that may require more resources being used such as keeping your CPU at a high level ? If none of these seems to be the problem than maybe you`re right, it could be a virus...

Millions of computers do get infected every week or month with new versions of malware: viruses, trojans, worms etc...Sure there is a difference between malware which is a program designed to steal, destroy and modify your system and the regular tracking cookies which we can refer them as related to our privacy. They may be harmless to our computers and it`s true they are actually tracking your habits but they can`t be held responsible for high computer resources.

When you get hit by a virus or any other form of malware you can check for one of the following signs :

- unusual high computer load and Internet traffic: possibly an infection with a virus that installed a rootkit and a bot ( a program ) which uses your computer for criminal activities such as: sending spam, using your computer as a scanning machine for similar computers as yours, tracking your computer usernames and password etc..
- unable to open some types of files such as .exe : probably a virus that will infect all executable files which has only one purpose to destroy all kind of files.
- unable to visit popular antivirus websites such as, or others: a lot of malware programs were designed to block users from getting access to antivirus solutions and they are blocking users access to such websites. It`s like having a phone in your house and when you`re trying to call the police, the thief would hear you before dialing and it would cut your phone wire.

- all kind of strange activity that you`ve recently noticed at your computer that never happened before: when this happens, it`s time for an investigation.

When you suspect that something bad happened the best thing to do is to react immediately. First thing to do would be to change your e-mail passwords, bank account login information ( if any ), Paypal passwords and any other sensitive information from another computer ( not from the one you suspect ). You don`t have to run with your car at a good friend as this is not the end of the world, it`s easier  and way faster to call your bank and ask them a couple of details about your bank account such as your current balance, recent transactions and I guess that they could also put a hold on your account until you will finish your investigation.

Second, as a confirmation try to install, update and run a scan with at least three different security tools. Here`s what I would run on my computer ( if it`s possible of course! ).

A. A good antivirus, my favorite antivirus for the moment is Avira Antivirus Premium which you can also use as it`s fully functional for a period of 30 days so feel free to use the trial version. Other antiviruses that I also recommend would be Kaspersky Antivirus or Dr. Web. So install any of them ( not all of them just one ) update them and perform a full scan of your computer. If you`re completely paranoid ( I am ) install one antivirus, update it, perform as I said a full scan of your computer, see the results, take action and then uninstall the antivirus. Take the next antivirus and in this way you can test all of them and see which one suits your needs. It will require more time and work but at least you will gain confidence, experience and you will discover the next antivirus that you`re going to use just in case that you`re looking for another antivirus solution.
Avira Antivirus Premium 2012
B. An anti-malware
software that has a high rate of detection. I highly recommend it! Ever since I got it,it has been my  favorite anti-malware tool - SpyBot Search and Destroy. Did I mentioned that it`s completely free ? Download it, update it and run a full scan.

Spybot - Search and Destroy 1.6.2 
C. Another anti-malware tool which is called Sophos Anti-Rootkit, download it, install it and perform a scan, make sure that you check all areas that you`re being allowed to select. This tool is focused on detection of rootkits. A rootkit is a program created by the bad guys with one purpose: to give them access to your computer and to allow them to install anything they want. The rootkit should also be completely invisible for you and for other security tools.

Sophos Anti-Rootkit version 1.5.20If nothing has been detected it`s either a recent virus that can`t be detected ( it happens ) or it has been well hidden and it`s almost invisible for most security tools ( temporary - could mean days, weeks or months ). Regardless of your results, infection or not, for your piece of mind I would recommend you to perform a full reinstallation of your operating system. This means that you will need to format your computer ( you may want to create a backup - save important information, preferably on one or more DVD`s as you can access them later. Right after the fresh installation, first thing to do is to install a good antivirus software, if you already had an antivirus and you got infected I would recommend you to change it. Using an additional malware tool right after the new installation such as SpyBot Search and Destroy and performing a system ``Immunization`` will usually help. Other things would relate to how you understand computer and Internet security so you just need to learn more about security. There are a lot of things to be done in order to increase the protection level of your computer.

Follow HowToAnswer