In this tutorial we will try to describe some symptoms that can make us suspect that your computer is infected. The main problem is that there are thousands of viruses that are manifested in very different ways, and that some symptoms that may also occur for other reasons.
In general, as an operating system begins to show failures overnight for no apparent reason. Before any strange behavior it is best to have a good antivirus, anti spyware and anti malware, but this is something that should make systematically every few minutes, because there are some viruses that do not produce visible effects in our system, and especially when it comes to high-performance computers.
The first thing we must keep in mind is that all operating systems can be infected by a virus. It is true that systems are safer than others, but there are none that really is immune, especially if we consider that many of these viruses are installed due to voluntary actions of the user.
Although some may seem illogical, is not exceptional that a user force the installation of a program even though a virus is telling him that a file is infected or to disable security measures, including antivirus, because the system allows you to download a file.
We will see below some symptoms that can present our computer, all indicative of the presence of a virus:
Computer is slowing down
This is a typical symptom, especially spyware. The slowing down of a system may also be due to other causes such as excessive temporary files, too many processes running or excessive load on startup, but in those cases usually notice a gradual slowing down, not suddenly.
Unreasonable loss of disk space
Typical especially worm-type virus (worm), which plays up to lock the system. It should be recognized as unjustified, because Windows creates a series of hidden and system files which can be quite heavy (even reaching enough GB). These files are going to occupy space, but always within limits and only the drive that contains them (usually the OS is installed), no other units.
Windows functions stop working or become inaccessible
Here we must differentiate not exist from the facility, which is a symptom of pirated versions of Windows, that, having been there and running smoothly, suddenly disappear or we will not let us access them.
The latter is usually due to actions of the virus so as to protect this system, since the functions which are often disabled are those that can help us fight the virus, such as System Restore, edit registry and like those.
Denial of Service
Is another type of virus attack. What causes the inability to load certain Windows services.
Unable to run antivirus, anti spyware and anti malware
This is a defense system of many viruses, disabling the execution of any program that can attack them. This item includes the inability even to download and / or install.
Loss of picture and sound properties
Although obviously a driver or a video or sound card can fail, the truth is that it is very normal to happen. In many cases the loss of audio and / or display properties are due to virus action.
Loss of units
This is another possible symptom of the action of a virus or malware. Sudden inability to access USB or optical drives (CD and DVD), especially if simultaneously, may well be due to the action of a virus. True, it may be due to a fault, but since it was handled differently and for different drivers (drivers), is quite rare that the two systems become inoperative simultaneously.
Loss of system files
A system file is not lost (or deleted) like that. In most cases viruses are responsible for this.
Internet connection speed is not justified
Excessive network traffic, without apparent justification, is usually a clear sign of infection. It is true that Internet traffic is almost continuous, but not about excessive traffic, and less likely to cause strange behavior and large loss of speed.
Occurrence of unsolicited web pages
This ranges from the uncontrolled opening up unsolicited page redirects to other pages than we have indicated.
Programs that use the internet stop working or begin to malfunction for no apparent reason
This affects mainly browsers and instant messaging programs.
Can not save files downloaded from Internet
Another symptom of infection. You can download a file or program, but is not recorded on the hard drive and can run (if that option was chosen to download the file).
Lockups and restarts the computer
A blockage can also be caused by excessive temperature (the way they protect processors in these cases), but a reboot is rare. If temperature conditions are normal, both locks and reboots are usually symptoms of the existence of some kind of malware.
Windows can not start
This is due to a bug in the operating system, but this bug is caused most often by the action of a virus. A difference is always in these cases the inability to start Windows with the inability to boot the computer and the possibility of a hardware failure, we also can prevent you start Windows, but in this case or the fault is detected by the BIOS or While Windows shows us through one of his now famous Windows blue screen of death (BSOD).
Actually this is one of the worst situations, and being unable to start Windows can not remedy the situation. However, in the tutorial Booting a computer affected by a virus we can see some ways to solve at least the initial problem, ie Windows startup.
We are asked for a password that we have not
This really is always motivated by a virus. The problem always starts with our own, so that in the beginning, you can enter safe mode, with the Administrator user (that in the event that this is not the user you’re using, a custom not recommended), but is gradually prevented from entering into any account, and also the passwords are random, which greatly limits the possibilities for disinfection.
Disappearance of files, inability to access folders or even drives
It is another symptom that can be motivated by an infection. In normal conditions, but a hardware failure or file away for good or a folder or drive are inaccessible.
Changes in the properties of some files
For just as the previous case. The properties of a file, folder or drive are not changed by hook, so that any of these behaviors can be a sign that we have one or more viruses on your computer.
The system does not allow certain programs
Unless problems caused by a fault in the hardware, a program is not so easily corrupted. The inability to run any program that we used regularly without problems can also be a symptom of an attack. This is more evident if the damage is not limited to a single program.
Loss of hard disk access
Although there are many viruses that can cause this situation (and talk about lack of access, not the system unbootable), yes there are some who do. Fortunately this situation is resolved by restoring the MBR (Master Boot Record), we can do from the Windows Recovery Console, running fixmbr, starting from the Windows installation DVD.
Well, so far we have seen some signs of possible infection by viruses or malware of some kind. I know that in many cases it is normal to blame Windows, but let’s not get carried away by false precepts. Windows or corrupted so easily without the intervention of others or is so unstable. In 98% of cases in which failure (and I mean, obviously, Windows legal, not pirated copies of more dubious origin), the failure is related to some kind of malware or user intervention, which sometimes happens in their handling, in many cases lacking the minimal knowledge.
Let’s take a look now to system failures that are attributable to viruses.
Here are included, for starters, all the computer’s startup failures (NOTE, not on startup). Normally, a virus has no way to access the BIOS and, therefore, infect. For this, the virus would have to go through an upgrade, for which you need a specific program, not executable from Windows. Keep in mind that the BIOS works at the hardware level, before the operating system loads. To this we must add the very few viruses that have evolved to infect (none currently active, including CIH). Another thing is that the BIOS is damaged, as it may damage any computer component.
However, in the highly unlikely case that a virus were to infect the BIOS, the only existing solution is to either change or change the motherboard. A reset of the BIOS is not going to serve anything in this case, or reload the original BIOS, which most likely is not going to leave or do.
Nor is it attributable to lack of virus detection units by the BIOS. In this case it is always a physical problem (usually a bad connection, damaged hard disk plate or failure of the motherboard).
Well, as you can see, the symptoms presented by a virus vary greatly, but unfortunately, and as I said, there are some viruses that do not have any symptoms, making them especially dangerous.
It is for this reason that we should always take a series of measures, since there are free, involving no extra expense to the user. These measures are:
– Install a good antivirus (Very good free option is Microsoft Security Essentials).
– Install a good anti spyware and anti malware (Malwarebyte’s Antimalware).
– Having them always updated correctly.
– Windows always have updated correctly, especially Windows Defender (if you have installed, nothing more than recommended).
** It is true that some updates, both antivirus and Windows, have caused some problems in specific settings, not in general terms, but these problems are always much smaller and easier to fix than any virus can cause us PROBLEMS.
– INTERNET WEBPAGE ALERT OF “FAKE” ANTIVRUS SAYING “YOUR SYSTEM IS INFECTED” OR “YOU HAVE REGISTRY ERRORS”: These ads are almost always a gateway to malware, including Trojans and spyware.
– WHAT TO DO IF INDICATIONS OF THE VIRUS THAT HAS ALREADY INTRUDED IN TO THE WINDOWS OPERATING SYSTEM : Nothing will serve us than to install the best antivirus program then if we ignore their directions, and the same goes for Windows alert messages.
– At the first signs of a possible virus, conduct a thorough scan of your computer, first with our anti-virus and other malware, and then a different online antivirus manufacturer. This means that, for example, if we installed Panda antivirus online scanning with Panda not to do so Online, however good.
– If you use a wireless router, always encrypt it and change the password to access the router setup. If it is encrypted immediately change the default key that brings. These keys are either generated automatically, and therefore a predictable pattern, or are as innocent as those used by a supplier, consisting of 26 0 or 26 1 (“it is safe?).
And always remember that our problems usually does not end when we have disinfected the computer. We’re really one of those cases where prevention is better. We must keep in mind that the cost of virus damage amounts to many billions of Dollars a year.?