Malicious software (malware) What Unauthorised software designed to cause harm Malware is a blanket term for malicious software including viruses, spyware, trojans and worms. Why Disrupt. Damage. Deceive. Typically, for profit. Malware gains access to important information such as bank or credit card numbers and passwords. It can also take control of or spy on a user’s computer. What criminals choose to do with this access and data includes: Theft Activism Espionage Other serious crimes Who Anyone, anywhere Malware creators can be anywhere in the world. They just need a computer, technical skills and malicious intent. Criminals can easily access cheap tools to use malware against you. It is not personal – they are not targeting you specifically – it is just business. Microsoft Defender Antivirus Microsoft Defender Antivirus is a built-in malware scanner for Microsoft Windows 10. As part of the Windows Security suite, it will search for any files or programs on your computer that can cause harm to it. Defender looks for software threats like viruses and other malware across email, apps, the cloud, and the web. A malware scan is as effective as its last definition update, which means if it is not updated regularly it may be unaware of and unable to detect newer forms of malware. Microsoft Defender Antivirus is updated when Microsoft Windows 10 is updated, which is why automatic updates should be turned on. To turn on automatic updates for Windows 10, please refer to our guide Turning On Automatic Updates (for Windows 10). Performing a malware scan with Microsoft Defender Antivirus Select the Windows icon in the bottom left of your screen and then click on the Settings Cog icon. Once in Settings, click on the Update & Security icon Click on Windows Security tab. Under the Protection areas section, click on Virus & threat protection. Under Current threats section, click on Scan options. Here you have four different scan options to detect malware. It is recommended to save and close your files before starting a scan. While you can continue to use your computer during some scans, this may lead to inaccurate results and you could experience issues with speed and performance. Once you have selected your Scan, click Scan now. You will see the progress, estimated time remaining and other information once you start the scan. When finished, you will receive summary information from the scan. In the event that the summary information identifies malware click Start actions and follow the on-screen prompts to remove the malware. Content complexity Simple This rating relates to the complexity of the advice and information provided on the page.