If you are looking for ways to remove W32.Downadup.B, then, you can find it on this page. Free tools and removal procedure is also included to get rid of the Trojan instantly.

W32.Downadup.B is a worm that propagates and infects computers by exploiting the Microsoft Windows Server Service RPC Handling Remote Code Execution Vulnerability. W32.Downadup.B will reduce security settings of compromised computer by ending security-related process and blocks them from accessing security websites. This worm will spread on unsecured network shares and removable USB drives.

Alias: Win32/Conficker.A, Mal/Conficker-A, Trojan.Win32.Agent.bccs, Worm:Win32/Conficker.B

Damage Level: Medium

Systems Affected: Windows 9x, 2000, XP, Windows Vista

When W32.Downadup.B is executed, it will attempt to copy itself under System folder of Windows as a hidden file. To evade anti-virus detection, the worm will use random file name. This worm will also make a duplicate copy on the following locations:
%ProgramFiles%\Internet Explorer
%ProgramFiles%\Movie Maker

To make sure that the file will run on every Windows start-up, W32.Downadup.B will create this registry entry.
HKCU\Software\Microsoft\Windows\CurrentVersion\Run = “(random characters)”

Presence of this worm may cause the computer to misbehave. The worm will perform various harmful tasks including the following:

  • It will modify system settings to restrict access to some files and folders.
  • The worm may disable TCP/IP services.
  • This worm will generate its own service and run once Windows is started.
  • W32.Downadup.B deletes system restore point and prevents running Windows System Restore.
  • Monitor Internet activities of the infected computer.
  • The worm may subsequently connect to a predefined URL to download arbitrary files.

The worm can be downloaded from unknown web sites without users consent. It attempts to exploit security breaches in Windows Server service to penetrate victim’s computer.
W32.Downadup.B commonly spreads and infects other computers on a network environment. It will dropped a copy of itself on all network mapped drives and removable devices. To trigger an autoplay when the drive is accessed, it will include Autorun.Inf that launches the worm.

W32.Downadup.B detection

How to Remove W32.Downadup.B

Systematic procedures to get rid of the threat are presented on this section. Make sure to scan the computer with suggested tools and scanners.

NOTE: We suggest that you PRINT or BOOKMARK this guide. There are steps that we may have to restart the computer in order to successfully remove the threat.

Optional : Scan and remove W32.Downadup.B with this special tool

1. Download the Downadup removal tool from this link and save it on your Desktop or any accessible location.

This tool is available free. It can delete members of the Downadup family of Trojan. The tool is created with removal function; it cannot protect the computer from threats.

Download bd_rem_tool.zip

2. Double click on downloaded file, chose "Extract all files..." from the File menu, and follow the wizard's instructions. You can use any other archiver, like WinZip. This will create a folder called bd_rem_tool.

3. Double click on the file "bd_rem_tool_gui.exe" (or just "bd_rem_tool_gui"). Make sure that all files have been extracted from the zip archive, because all the contents are required for the removal tool to run. Follow the tool's instructions.

4. If you have Restricted Access (not Admin) on Windows Vista and XP, right click the "bd_rem_tool_gui" program and choose "Run as Administrator". Enter the computer Administrator User name and Password when prompted. This will scan the computer for presence of W32.Downadup.B. Remove all detected threats.

Scan in progress

5. Reboot your computer when scanning is finished.

Step 1 : Run a scan with your antivirus program

1. Remove all media such as Memory Card, cd, dvd, and USB devices. Then, restart the computer and please do the following:

Boot in Safe Mode on Windows XP, Windows Vista, and Windows 7 system
a) Before Windows begins to load, press F8 on your keyboard.
b) It will display the Advanced Boot Options menu. Select Safe Mode.

Start computer in Safe Mode using Windows 8 and Windows 10
a) Close any running programs on your computer.
b) Get ready to Start Windows. On your keyboard, Press and Hold Shift key and then, click on Restart button.
c) It will prompt you with options, please click on Troubleshoot icon.
d) Under Troubleshoot window, select Advanced Options.
e) On next window, click on Startup Settings icon.
f) Lastly, click on Restart button on subsequent window.
g) When Windows restarts, present startup options with numbers 1 - 9. Select "Enable Safe Mode with Networking" or number 5.

Startup Options

h) Windows will now boot on Safe Mode with Networking. Proceed with virus scan as the next step.

2. Once Windows is running under Safe Mode with Networking, open your antivirus program and download the most recent update. This method ensures that your antivirus program can detect even newer variants of W32.Downadup.B.

Updating your antivirus software is a one-click process. Please refer to your software manual for complete instructions.

3. Once updating is finished, run a full system scan on the affected PC. After the scan, delete all infected items. If unable to clean or delete, better place the threat in quarantine.

Step 2: Run another test with online virus scanner

Another way to remove W32.Downadup.B without the need to install additional antivirus software is to perform a thorough scan with free online virus scanner. It can be found on websites of legitimate antivirus and security provider.

1. Click the button below to proceed to the list of suggested Online Virus Scanner. Choose your desired provider. You can run each scan individually, one at a time, to ensure that all threats will be removed from the computer. This may require plug-ins, add-on or Activex object, please install if you want to proceed with scan.

Online Virus Scan

2. After completing the necessary download, your system is now ready to scan and remove W32.Downadup.B and other kinds of threats.
3. Select an option in which you can thoroughly scan the computer to make sure that it will find and delete entirely all infections not detected on previous scan.
4. Remove or delete all detected items.
5. When scanning is finished, you may now restart the computer in normal mode.

Alternative Removal Procedures for W32.Downadup.B

Option 1 : Use Windows System Restore to return Windows to previous state

During an infection, W32.Downadup.B drops various files and registry entries. The threat intentionally hides system files by setting options in the registry. With these rigid changes, the best solution is to return Windows to previous working state is through System Restore.

To verify if System Restore is active on your computer, please follow the instructions below to access this feature.

Access System Restore on Windows XP, Windows Vista, and Windows 7

a) Go to Start Menu, then under 'Run' or 'Search Program and Files' field, type rstrui.
b) Then, press Enter on the keyboard to open System Restore Settings.


Open System Restore on Windows 8

a) Hover your mouse cursor to the lower left corner of the screen and wait for the Start icon to appear.
b) Right-click on the icon and select Run from the list. This will open a Run dialog box.
c) Type rstrui on the 'Open' field and click on OK to initiate the command.


If previous restore point is saved, you may proceed with Windows System Restore. Click here to see the full procedure.

Option 2 : W32.Downadup.B manual uninstall guide

IMPORTANT! Manual removal of W32.Downadup.B requires technical skills. Deleting system files and registry entries by mistake may result to total disability of Windows system. We advise you to perform a backup of registry before proceeding with this guide.

1. Kill any running process that belongs to W32.Downadup.B.

- Press Ctrl+Alt+Del on your keyboard.
- When Windows Task Manager appears, look for W32.Downadup.B files (refer to Technical Reference) and click End Process.

End Task

2. Delete all registry entries that belong to this malware.

- Press [Windows Key]+R on your keyboard.
- In the 'Open' dialog box, type regedit and press Enter. This will open registry editor.
- Find and delete the following:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "[random charaters.exe]"
- Close registry editor. Changes made will be save automatically.

Run Regedit

3. Scan the computer with antivirus program.

- Connect to Internet and open your antivirus software. Please update to obtain the latest database and necessary files.
- Restart the computer in Safe Mode using the procedures above.
- Open your anti-virus program and thoroughly run a scan on the computer. Delete/Quarantine all identified threats to remove W32.Downadup.B effectively.

4. Delete all files dropped by W32.Downadup.B.

- While still in Safe Mode, search and delete malicious files. Please refer to 'Technical Reference'. Make sure that you execute 'End Task' first before deleting the file. Otherwise, the system will not let you perform this action.

Associated Files and Folders:
File Location for Windows Versions:
  • %System% for all versions of Windows it is located under C:\Windows\System32
  • %Temp% refers to C:\Windows\Temp\.
Added Registry Entries:

Ways to Prevent W32.Downadup.B Infection

Take the following steps to protect the computer from threats. Suggested tools and security setup within installed software helps prevent the same attack on your PC.

Install an effective anti-malware program

Your first line of defense would be an effective security program that provides real-time protection. We have a list of anti-malware program that are tried and tested. It does not only scan files but also monitors your Internet traffic and is extremely active on blocking malicious communication. Click on the button below to download our recommended anti-malware program.

Get Protection Software

Always update your installed software

Software vendors constantly releases updates for programs whenever a flaw is discovered. Getting the updates makes the computer more secured and help prevents Trojan, virus, malware, and W32.Downadup.B similar attacks. If in case your program is not set for instant update, it usually offered from vendor's web site, which you can download anytime.

Maximize the security potential of your Internet browser

Each browser has their own feature where in you can adjust the security settings that fit your browsing habit. We highly encourage you to maximize the setup to tighten the security of your browser.

Apply full caution when using the Internet

Internet is full of fraud, malware, and many forms of computer threats including W32.Downadup.B. Implement full caution with links that you may receive from emails, social networking sites, and instant messaging programs. It might lead you to malicious sites that can cause harm to your computer. Avoid strange web sites that offers free services and software downloads.

22 Responses

  1. precisesecurity says:

    1. Temporarily Disable System Restore (Windows Me/XP/Vista/7) . [how to]
    2. Update the virus definitions.
    3. Reboot Windows in Safe Mode. [how to]

    4. Find and Stop the Service:
    – Click Start > Run.
    – Type services.msc, and then click OK.
    – Locate and select the service that was detected.
    Service name: [PATH TO WORM]
    Startup Type: Automatic

    – Click Action > Properties.
    – Click Stop.
    – Change Startup Type to Manual.
    – Click OK and close the Services window.

    5. Run a full system scan and clean/delete all infected file(s)
    6. Delete/Modify any values added to the registry. [how to edit registry]
    Navigate to and delete the following registry entries:
    HKEY_CURRENT_USER\Software\Microsoft\Windows\Current Version\Run\”[RANDOM NAME]” = “rundll32.exe “[RANDOM FILE NAME].dll”, ydmmgvos”
    HKEY_CURRENT_USER\Software\Microsoft\Windows\Current Version\Applets\”dl” = “0”
    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\Applets\”dl” = “0”
    HKEY_CURRENT_USER\Software\Microsoft\Windows\Current Version\Applets\”ds” = “0”
    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\Applets\”ds” = “0”
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\[WORM GENERATED SERVICE NAME]\”ErrorControl” = “4”
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\[WORM GENERATED SERVICE NAME]\”ImagePath” = “%SystemRoot%\system32\svchost.exe -k
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\[WORM GENERATED SERVICE NAME]\Parameters\”ServiceDll” = “[PATH TO WORM]”

    Restore the following registry entries to their previous values, if required:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\ “TcpNumConnections” = “00FFFFFE”
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Current Version\explorer\Advanced\ Folder\Hidden\SHOWALL\”CheckedValue” = “0”

    7. Exit registry editor and restart Windows.
    8. In order to make sure that threat is completely eliminated, carry out a full scan of your system using AntiVirus and Antispyware Software. Another way to delete the virus using various Antivirus Program without the need to install can be done with Online Virus Scanner.

  2. precisesecurity says:

    1. Download removal tool from this page and save it on your Desktop.
    2. After downloading, double-click on to install the application.
    3. Follow the prompts and install as “default” only
    4. If it prompts to update the database after installation, please proceed.

    5. Click “Finish.” Program will run automatically and you will be prompt to update the program before doing a scan. Please update.
    6. Scan your computer thoroughly.
    7. When scanning is finished, click on the “Show Results”
    8. Make sure that all detected threats are marked, click on Remove Selected.
    9. Restart Windows.

    Note: Some malware may prevent mbam-setup.exe from downloading and running. You can download and rename this program from a different computer before running it on infected system.

  3. Mahesh Babu says:

    There is no perfect removal until now. Eithere Microsoft or Symantec needs to release any thing.
    Symantec released one removal which is useless as of now.
    Lots of machines are ffected until now. So guys wait and see for the removal.
    ‘Til then, sit in front of PC and search.

  4. Aleem Asghar says:

    Hi All,

    My Network in also infected from W32.downadup.b virus, I tried malwarebytes, noadware5 and spyware terminator, I also have tried all that was given at Symantec site for removal. Please help me if any one of you find the solution.

    Thanks and regards,

  5. Pakistani says:

    I was infected by this virus then I reinstalled my Windows and Norton AV. But next day it again attacked. Any one here experienced the same?

  6. jackie says:

    I had encountered the same problem. Try to check your task scheduler, the virus will create the tasks every single 30min – 1 hr and it will create a lot of rundll32.exe service at back end process.
    Remove the tasks in task schedule and disable the task schedule in services.
    Go to Safe Mode, Run the patch given by Microsoft and then run tool from Symantec and virus removal from Microsoft (for double confirmation) and then run the patch again.
    After those steps, you should be safe.

  7. Ramila says:

    Hi All,

    My Network in also infected from W32.downadup.b virus, I tried malwarebytes, noadware5 and spyware terminator, I also have tried all that was given at Symantec web site for removal. Please help me if any one of you find its solution.


  8. Aman says:

    To protect from all boot, malware and etc etc viruses on Windows machine.
    1. Use a user which does not have administrator rights for day to day use.
    2. With the Administrator User Install Malwarebytes’ Anti-Malware.
    3. Install Quick Heal Antivirus..

    You will be free from Viruses and Malware for a long time.

    Some times in Malwarebytes Scan you will find a thing and ask to restart the machine. After restart still you will again see the same malware in Quick Scan. TO remove that you will have to use a tool as “Hijack This”..

    azizmujawar @ yahoo.com

  9. Asif says:

    If you are using symantec End point , as it catches this virus simple click to “view quarantine” and delete.
    This will resolve issue.

  10. puli says:

    My network is also attacked by this w32.downadup.b virus, I have followed the steps given by symantec and f-secure tools no use. even I tried with Microsoft malicious tool and I updated the hot fix also. No use guys, now I am going to check with noadadware and quickheal tool. Please help if you find any good tool to remove this one from network

  11. Sunil J says:

    Hi Friends,

    I am also facing same problem in my Network, I am using Quick Heal Total Security 10.0, but is unable to completely clean from system. Is there any one having successful methods or tools for clean such viruses.

  12. Shahid says:

    Hi all,
    I have also this worm on my network. I have symantec 9. I installed Symantec 10 on one system that is detecting and quarantine the files.I format 2 systems but just after I connect my system with Internet by LAN to update windows I cannot update, Live update is disabled and on that system I cannot update symantec 10 also. Now this virus is sending messages on other systems with the system name that a virus has detected.
    Please provide solution.

  13. Mecca Soul says:

    Hey All,

    I had the same problem on my network and I found a way to get rid of it totally. The first thing you need to do is check to see if you can get to symantec.com or microsoft.com. If you can’t you are probably infected. Another way of checking is to go to your registry and look for a funny looking entry in one of your settings.
    Go to a machine that you know is not infected and go to this Microsoft knowledge base: http:// support.microsoft.com/kb/962007
    follow the path that they give you in step 7 of the manual removal…this will at least let you know if you have the virus.
    Download the removal tool from Symantec – www. symantec.com/content/en/us/global/removal_tool/threat_writeups/D.exe.
    It works trust me. Burn it to a cd if you can because the virus travels through usb keys if the autoplay is not turned off.
    Follow the rest of the microsoft removal instructions
    It does not catch the worm all of the time. Symantec’s tool works if you know the PC is infected.
    -Good Luck!!!

  14. sNkr says:

    I am trying to remove W32.Downadup.B from my network. None of the tools work.
    It’s getting worst day by day.

  15. Iqbal says:

    I am using windows 2003 server.I have 37 client computer.32 computers for the game.Lan game .Online game.5 computers for internet.i use Netcraft software for my system.In my server all the time W32.Downloadup.B …Location….Windows\system32\x.

    But I tried so many thing still having problem.always autoprotect result comes to desktop.

    anyone can help me pls pls pls ……

    Thank you

  16. Slow Poizon says:

    I don’t think so that there’s any perfect tool available i tried almost everything… but still… No Good News…

  17. chong says:

    i am using window server 2003. anyone know how to clear w32.downadup.b? i have try Malwarebytes’ Anti-Malware and doctor spy but still cannot remove this virus…anyone can help?

  18. sunil singh says:

    i am trying to remove W32.Downadup.B from my network. None of the tools work.
    Its getting worst day by day..


    Thanks in advance

  19. tony says:

    i removed with KK.exe form microsoft kaspersky

  20. Bhupesh Kumar says:

    I am using ISA server with symantec endpoint protection and symantec detects this virus w32.downadup.b many times in a day. although it deletes the virus but i still wanna know why does it detect this virus again and again??

  21. shokendra kumar says:

    i have a antivirus server of symentac 11.0, it update daily basis and scan also but an antivirus is not remove on network – downadup. it find in many nomber and save in quarentine directory.

    so give me some sagetion for remove it on network

  22. khaleel ahmad says:

    pleez help me

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