Option A — Standard installation
Download
Get Trojan Killer from our official download link.
Open the installer
Double-click the downloaded file and approve the Windows prompt (UAC) to continue.
Choose setup options
Select the install location and (optionally) create a desktop shortcut, then click Install. Agree to the EULA
You can also read the EULA on our website.
Click Finish. You can auto-start Trojan Killer right after setup. On first run, let it update the threat database.
Option B — Use the Portable Edition (no installation)
Use this when the PC is restricted, heavily infected, or you prefer to run from a USB stick.
Prepare on any clean PC
Download Trojan Killer and place (or install) it onto a USB flash drive.
Plug into the target PC
Connect the USB and launch Trojan Killer directly from the USB—no installation needed.
Update & scan
Start Trojan Killer from the USB, update definitions if you’re online, then run a scan and follow on-screen actions. (A restart may be required to finish removals.)
System requirements
Windows 11/10 (32/64-bit)
Legacy compatibility:
Runs on Windows 8.1/8. Many shops and legacy PCs still need malware cleanup. Trojan Killer can run on Windows 7/Vista/XP too, with reduced features on those unsupported systems.
Why: Microsoft no longer supports 8.1/8 with security updates, so we keep them as “works if you need it,” not primary targets.
Verify you downloaded the legitimate app (recommended)
Official source: Always download from Gridinsoft domains.
Digital signature: In Windows, right-click the file → Properties → Digital Signatures to confirm it’s signed by Gridinsoft LLC.
Activate your subscription
If you already have a code or license, follow the activation guide after installation/first launch.
If the installer won’t start
Run as administrator: Right-click the installer → Run as administrator.
Temporarily pause other security software: Some products block third-party installers. Resume protection after install.
Try Portable Edition: If downloads or installers are blocked, prepare the USB on a clean PC and launch it on the target machine.