If you are a user who is interested in staying safe when surfing the Internet, it is very likely that you use an antivirus (I hope with all my heart that it is an official one), but of course, antivirus always have limitations to detect and / or block possible malware on your system and, it is one of the decisions why some users come to wonder Can I install more than one antivirus at a time in my operating system? in this article we will explain why this is a bad practice and try to make you aware not to do it.
Why can't you use two antivirus programs at the same time?
You have to understand the basics, antivirus are there to detect malware in your system and protect you, they work with signature detection and (most of them) with heuristics, which allow them to detect malware not by signatures but based on the behavior they have in the system, that is, if an application you install starts to behave abnormally doing actions in the system that are not typical of a legitimate software, if your antivirus has heuristics, it will possibly warn you of that software.
Starting from this idea, you will understand that, if an antivirus constantly scans your system and detects that a software (the other antivirus installed) is scanning the system as well, monitoring the connections you make to detect if any is malicious or not and in general doing actions that a software that is not an antivirus would not do, it will possibly detect it as a malware, because of course, the first antivirus does not know that this software doing these actions, is actually another antivirus, it just assumes that it is a software in the system that is doing actions that it should not, and that is where the problems can start, because when you install an antivirus, in itself, the antivirus assumes that there is no other antivirus installed and running actively, this if you use Windows you will see it because if you install a third party antivirus, Windows Defender stays “asleep” to not interfere and, even if you manually activate Windows Defender too, it will not offer you real time protection because there is already an antivirus installed doing it.
What can happen to my system if I use more than one antivirus at the same time?
First, if you currently have more than one antivirus installed, it would really be good that you stop reading and go to uninstall one of them, because the consequences can be several, among the main ones we have an obvious increase in consumption of system resources, because, although in the hypothetical case that both antivirus are not detected as malware each other, an antivirus by default consumes enough system resources (because it is obvious, it has to be monitoring almost all actions that are made) now, having more than one, also implies that consumption will increase.
On the other hand, what we commented a moment ago, that there is a false detection between any of the two antivirus or between both (which would be worse) where each antivirus would be fighting to eliminate the other giving you a scene like when Ultron tries to eliminate Jarvis in the second movie of the Avengers, only with less fiction because the antivirus do not speak and the consumption of resources that will have your system will be quite high, causing slowness.
As a conclusion, using more than one antivirus will not give you more security in your system, in fact, it can make the installed antivirus not work optimally and actually get the opposite, not protect you, you can always install and uninstall them when you want to scan the system with several antivirus and thus have several opinions but try to have active only one antivirus at a time.