Not all Trojans will install fake or rogue AV because there are also Trojan horses that will install keyloggers to record and steal your personal information such as credit card numbers, login credentials, passwords and other valuable data.
A computer worm is another type of malware that will use your computer to infect other people's PC in your network or spam your contacts. Worms often affects computers that are not protected with the latest security updates. Most worm creators will take advantage of unpatched security flaws in Windows (also known as Zero-day vulnerabilities). The infect computer may also become part of a botnet.
Viruses will replicate and reproduce by infecting other files in the computer, usually important files such as critical system files. It can infect other computers in the network or transfer through a removable drive such as a USB drive, floppy disc, CD or DVD.
If you suspect that the PC is infected by worms, computer viruses or a Trojan horse, use the following steps to clean the computer:
Please note that the above malware scanners in Removing Fake, Misleading or Rogue programs can also detect and remove Trojans, worms and viruses, but only use them if you have downloaded the anti-malware tools and its latest detection updates using another computer. Keeping your internet connection active may cause infection to other computers or infection of the tools themselves.
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