Is your system running slow? Are you experiencing pops up or a blank screen with no icons and taskbar? More than likely, your system has become infected with malicious software-it can be worm, virus, trojan horse, redirectors and some form of malware. These are the common indications that your system may have been infected with these so called malware. It is an unfortunate situation to be caught in if your system locks up and you can't do anything at all, especially If you have a bunch of important files saved to your computer. If this is the case, you might need to consider having a professional virus and spyware removal service provide immediate assistance.
There are many ways our systems can become infected. The most common culprit would be the Internet. Sometimes, the virus can disguise itself under a different website so people will think it's the usual website that you visit and end up having infections. It can also be transferred through mail attachments or through a USB thumb drive that has infected files. What these infections do are they disable or hijack your antivirus program and do it's subtle attacks-they tamper some settings on the registry, set restrictions and policies on our systems hence we can't access some files and some functions/features are not working. Furthermore, these can also cause series of blue screens or loop as we log in.
The most common file extensions that viruses attack are .exe, .sys, .dll and other file extensions on Windows library... It may also delete some important Windows component that may result in your computer being unable to start up. One important file is the userinit.exe file under system32 folder, when this file is deleted it will not load the settings for a certain user and will just log off.
People think that systems are not prone to have infections once there is an antivirus program installed. This is a common misconception where in fact, there is no perfect antivirus program that can give a hundred percent protection but it still depends on what users do and how it's being used. One way to prevent having a virus infect your computer is to limit the amount of visits to unsecured websites. Nevertheless, as users we still have the power over this to protect our systems and prevent this from happening.- we can update our antivirus online regularly, clear cache/cookies or run some cleaning tools for this. Do a scan on USB flash drives and mail attachments before we open it. Most of all, we should be careful and vigilant on things that we browse online.