How do I know if my computer is infected?
I will explain both methods to find out if the computer is infected.
These two methods are very different, one based on the program and the other based on research and/or knowledge. The first is the simplest and easiest, while the second gives you safer results.
Method 1: Use a security programIf you have an updated antivirus or firewall, they will do a good job. Also, as soon as you suspect a program on your computer, you must run an antivirus scan before testing anything else.
This is usually enough to detect and remove any viruses. In other cases, chances are you feel that someone has entered your computer even though your antivirus did not detect anything.
A completely opposite case may occur: your antivirus / antispyware (besides potentially not detecting threats) can detect you all sorts of issues that are strangely called threats while they are not.
Famous PUP (Potentially Unwanted Program) programs and their PUA or PUP versions are often mass-detected by some tools, making the user believe he or she is infected, while this is not the case.
If this is your case, you can download a program that is slightly more designed to remove certain programs like the infamous Trojan Remover to remove Trojan Horse.