Portable Virus Scanners for Windows

TL;DR

Yes, several virus scanners for Windows can run without a full installation – these are often called ‘portable’ scanners. They’re useful for quick checks on systems where you don’t want to install software permanently or need to scan from removable media like USB drives.

How to Run Virus Scanners Without Installation

1. Understand Portable Scanners: These scanners run directly from an executable file (.exe) and typically store their virus definitions within the same folder. They don’t modify the Windows Registry or install services.
2. Popular Options: Here are a few reliable portable virus scanners:
   • Kaspersky Virus Removal Tool: A free tool for one-time scans and removal of malware. Download from Kaspersky.
   • Emsisoft Emergency Kit: Offers a scanner and cleaner, also free for on-demand use. Available at Emsisoft.
   • Dr.Web CureIt!: Another excellent free option for detecting and removing threats. Get it from Dr.Web.
3. Download the Scanner: Visit the official website of your chosen scanner (links above). Always download directly from the vendor’s site to avoid fake versions containing malware.
4. Run the Scanner:
   1. Double-click the downloaded .exe file.
   2. You may be prompted by User Account Control (UAC). Click ‘Yes’ to allow it to run.
   3. The scanner will usually start automatically. If not, look for a ‘Scan’ or similar button within the program window.
5. Update Virus Definitions: Before scanning, always update the virus definitions. Most portable scanners have an option to check for updates when you first launch them. If not:
   • Look for a ‘Settings’ or ‘Options’ menu.
   • Find an ‘Update’ button and click it. This downloads the latest threat signatures.
6. Perform the Scan: Choose your scan type:
   • Quick Scan: Checks common areas where malware is often found (faster).
   • Full Scan: Scans all files on your system (slower, more thorough).
   • Custom Scan: Allows you to select specific folders or drives to scan.
7. Review and Remove Threats: The scanner will display any detected threats. Follow the on-screen instructions to quarantine, delete, or ignore them. Be cautious when deleting files – ensure they are genuinely malicious before removing them.
8. Using Command Line (Advanced): Some scanners offer command-line options for more control. For example, with Dr.Web CureIt!:

   drweb cureit /scan c:

   This scans the C drive. Refer to the scanner’s documentation for available commands.

9. Limitations of Portable Scanners:
   • Real-time Protection: They don’t provide continuous, real-time cyber security protection like a fully installed antivirus program.
   • Automatic Updates: You need to manually update the virus definitions regularly.
   • Scheduling: They typically lack scheduling features for automated scans.