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You can check for rootkits by running the Windows Defender Offline scan. This is one way malware can reappear after you’ve removed it. Rootkits act mainly as backdoors so that other programs, such as keyloggers and viruses, can be installed from remote servers. Users sometimes find out they have a rootkit because something odd – high processor usage or unexplained internet traffic – prompts them to check their firewall logs to find the culprit.
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It’s the kind of approach used to attack IoT (Internet of Things) devices, where recovery involves not only changing the software but updating the firmware. This was the first attack of its kind to affect Windows 10, but it could become more common.
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Late last year, ESET antivirus researchers found rootkit code hidden in the Flash memory of a PC’s Serial Peripheral Interface (SPI), where it could survive even if you did a clean reinstallation or changed the hard drive. Rootkit writers try to hide code in places where they can avoid detection. Rootkits are designed to avoid detection, sometimes for many years. Whichever route you take, start by running one or more programs designed to find rootkits and similar software. Rootkits can be a pain to spot and remove. Today, this seems to apply even if the only antivirus software you run is Microsoft’s Windows Defender. That includes my wife’s machines, and she has no interest in becoming a computer expert.Īssuming you run antivirus software and have a firewall turned on, you can generally avoid Windows malware by keeping all your software up to date – which I do – and by not making any silly mistakes. It’s well over a decade since malware affected any of the PCs in our house. Of course, it’s better to avoid having the problem. It’s also the best option if you are going to sell a laptop, or give it away. I recommend the nuclear option for bad virus infections and for laptops that only have 32GB of built-in storage. In this case, you can either use Windows 10’s built-in reset system or take the nuclear option of reinstalling Windows 10 from scratch.
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If you don’t have a lot of programs and data to restore, then a reset could be quicker. This can take quite a long time, but you don’t have to re-install all your programs and data.
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