How to remove Trojan Medfos.B Virus

My computer is running on Windows 7 and using Google Chrome as my browser. This issue of Trojan Medfos.B virus started after visiting a site to download some serials. Right after that, Microsoft Security Essentials alert me of infection on C:\Users\Owner\AppData\Local\chromeupdate.crx. It says that computer is infected with Trojan:JS/Medfos.B. MS Malware Protection Center described this Trojan as malicious Java Script, see it here. Thus, I already deactivated any Java Script on my computer and relevant activities but the virus persists.

MSE was able to detect it and removing it is obtainable with a click. However, after restarting the computer, the program issues the same alert about Trojan Medfos.B. I already updated the program to have the most recent database but the problem still exists. Any advice is highly appreciated.
Bill Torton


  1. sixtygb

    You can always download free virus removal tools like Norton Power Eraser, MS Malware Removal Tool, MBAM, SAS, and so on. If your present antivirus software is not detecting Trojan Medfos.B, better junk it. There are available programs to choose from that can surpass the performance of your antivirus software.

    Just a piece of advise. Keep away from cracks and serial web sites that offers file download. You don’t have to download a file to see the requested serial number. It should be posted right on the page. Most of all, be fair. Stay out of unlawful doings. Use only licensed product.


  2. Matthew

    U have a rootkit. My forefront finds it but cannot removethe rootkit thats feeding the file back into the system. Typically I’ll use MBAM and Unhackme combo to get it but they have been unsuccessful. Unhack wont run when I reboot to infected profile (users arent admins on our network) and MBAM says its finding nothing.

    I probably sould be doing this in safe mode but im remotely accessing this machine.

  3. Fajhar

    Remove AdAware from Start-up: Go To Computer/ Double-Click on Drive C /Double click on Program Files / Scroll down and look for any Adaware or Lavasoft files. Right click and delete them. Reboot. If that does not work, under Search in windows, enter either Adaware or Lavasoft and see what comes up. If anything comes up, DELETE IT. Excellent Luck. P.S. Download the latest copy of CCleaner and run both the Cleaner and Registry options.

  4. diana

    Forget what your antivirus can do. Remember that Trojan:JS/Medfos.B is detected by MS security software, therefore only MS product can find and remove it. Try using Microsoft Security Essentials that you can download from here:

    Other option you might try is System Restore. If you have a saved restore point before Trojan:JS/Medfos.B has infected the PC, better rebuild the system now. This method will not delete any personal files like docs, images, musing, and so on. It will only return your system settings to a previous point. Read more of the System Restore options for Windows from Microsoft web site.

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