Engadget Guide Outlines How to Check a Windows PC for Malware

The guide says users may suspect malware if a PC suddenly runs slowly, freezes more often than usual or shows strange processes. Windows 11 includes Microsoft Defender as part of the Windows Security suite, which can be found through the Start menu. Each icon shows a green checkmark when all is well, while yellow or red warning icons indicate concerns of different severity. The Virus & threat protection section is most relevant. Defender is turned on by default and scans regularly, with details of the latest scan shown at the top. The Allowed threats page lists flagged items a user has approved, and unfamiliar entries there can offer a clue to system issues. The Protection history tab logs when Windows Defender takes action.

Defender's quick scans only look where threats are commonly found, according to the guide. For a deeper check, users can choose Scan options, then Full scan and Scan now, which can take time depending on the number of files. The Microsoft Defender Antivirus offline scan option restarts the PC into the Windows Recovery Environment, where a scan is more likely to find malicious threats that try to cloak themselves. The guide also advises checking Firewall & network protection to make sure the firewall is on for all three types of connections. It says the default option of blocking incoming connections that have not been permitted is good in most cases, and that understanding how a VPN works can add another layer of protection.

The guide says Windows' built-in tools are a solid baseline, but it is smart to have at least one other anti-malware scanner, not a second real-time antivirus, to catch what Defender might miss. Malwarebytes, whose free version offers an on-demand scanner, can run a Quick Scan, a Custom Scan or a Deep Scan. If it finds anything, it alerts the user and offers options such as quarantining or deleting the threat. Malwarebytes also offers AdwCleaner, a separate free tool focused on adware and similar junk. Paid Malwarebytes subscriptions add real-time protection, browser scam-blocking and more features in higher tiers, though the guide says these are not usually necessary if users browse carefully.

Additional options include entering safe mode before running scans, because it provides a simplified environment without a network connection. Microsoft updates and runs its Malicious Software Removal Tool each month to detect and remove common forms of malware; users can run it manually by pressing Win + R, entering wrt and confirming the User Account Control prompt. Other second-opinion tools include ESET Online Scanner and Emsisoft Emergency Kit, while VirusTotal can check files or webpages for infection. The guide says replacing Windows Defender with a third-party antivirus is almost certainly unnecessary. Free third-party antivirus tools can provide good protection, it adds, but most have constant pop-ups urging users to upgrade to a paid version.

Editor's Summary Engadget's guide says Windows users can start with Microsoft Defender and then use on-demand tools such as Malwarebytes, AdwCleaner, ESET Online Scanner, Emsisoft Emergency Kit and VirusTotal for second opinions. It also points to full and offline scans, safe mode, firewall checks and Microsoft's monthly Malicious Software Removal Tool as additional steps. The guide concludes that replacing Windows Defender with a third-party antivirus is almost certainly unnecessary for most users.