Can The Installed M.D.A. Deal With A Trojan/s In 2026?

Question

Can my installed M.D.A. deal with a downloaded and or installed trojan/s, whether it was done accidentally and or done on purposely in 2026?.I ask this question because before 2026,both the W.D./M.D.A. used separately on their own, simply could not deal with a trojan/s?,and had to use another free antivirus that was able to deal with the very same trojan?. Should i be looking into installing a free trojan scanner or free malware scanner type program, as a second line of defense that can be run along side with the M.D.A.?

Answer 1

Microsoft Defender Antivirus (MDA) in Windows 10 and Windows 11 is designed to detect and remove a wide range of malware, including trojans, and continues to be updated in 2026 via security intelligence (definitions). It provides real-time protection to block malware (including trojans) from running, and on-demand scans to detect and remove infections.

Trojans are specifically called out as a common malware type that Microsoft tools detect and remove. Guidance for trojans is to use:

1. Microsoft Defender Antivirus (built into Windows 10/11)
2. Microsoft Safety Scanner as an additional on-demand scanner

For post-infection cleanup of certain prevalent malware families (including trojans, worms, and viruses), the Windows Malicious Software Removal Tool (MSRT) is also available. MSRT is a post-infection removal tool that targets only specific prevalent malware families and focuses on active infections; it does not replace a full antivirus product and does not remove spyware.

Regarding running additional security products alongside Microsoft Defender Antivirus:

• It is not recommended to run another real-time antivirus or antispyware product at the same time as Microsoft Defender, because multiple real-time products can reduce performance and cause update/installation errors.
• It is safe to run on-demand scanners (such as Microsoft Safety Scanner or Microsoft Defender Offline) alongside Microsoft Defender, because they only run when explicitly started or scheduled.

For layered protection in 2026:

• Keep Microsoft Defender Antivirus enabled and fully updated (definitions are updated via Windows Update; they can also be checked manually from Virus & threat protection → Virus & threat protection updates → Check for updates).
• Use Microsoft Safety Scanner or MSRT as additional on-demand tools if a trojan or other malware is suspected.
• Avoid installing a second real-time antivirus to run concurrently with Microsoft Defender; if another real-time product is installed, Microsoft Defender Antivirus will turn off.

This configuration provides a primary real-time defense (Microsoft Defender Antivirus) plus optional on-demand scanners as a second line of defense, including against trojans.

---

References:

• Trojans
• Antivirus and antimalware software: FAQ
• Consumer antivirus software providers for Windows
• Remove specific prevalent malware with Windows Malicious Software Removal Tool (KB890830)
• Protect yourself from online scams and attacks