Bluescreen Errors


Bluescreen Errors

Users may encounter bluescreen errors referencing "RfeCoSvc", "bwcW10x64", or "QCAmain10x64". These errors have been addressed with more recent versions of the Killer Control Center and the drivers included. You can download the latest Killer Control Center from here -

The Killer Control Center has replaced the Killer Network Manager, and the Killer Network Manager is no longer being developed. The Killer Control Center is fully compatible with the E2200, E2400, and the E2500, as well as all of our Wireless-N and Wireless-AC network adapters. 

For a smooth install, it is recommended that you:

  1. Download the latest installer, saving it in a place that you will remember.
  2. Right-click Start
  3. Click Apps and Features
  4. Uninstall all entries with the title of "Killer Suite," "Killer Drivers," or any variation of those titles. 
  5. Restart your machine by clicking Start > Power > Restart. Avoid using the power button on the computer, as it is likely mapped to sleep the machine instead of shutting it down.
  6. Once the computer has booted back up, run the installer that you downloaded for the latest Killer Control Center. 

If you encounter any problems in following the above steps, please see this article - Problems Updating Killer Control Center.

If you encounter blue screen errors while using the latest suite downloaded from this website, please contact support.


VPN Client Connectivity Issues


Shrewsoft and Other VPN Clients

Previous versions of the Killer Control Center had some issues with some VPN clients. These issues have been resolved with the current releases. 

We suggest you download the latest Killer Control Center, found here -

Keep in mind that the Killer Control Center contains our latest drivers, and supersedes the Killer Network Manager that you might find pre-installed on your machine from the manufacturer. 

Once you have the latest Killer Control Center handy, please follow these steps: 

Note: It is important to be aware that, when troubleshooting, you should always shut down your computer by clicking the Start button in the lower left-hand corner, clicking the Power symbol, and clicking Shut Down. You should always reset or reboot your computer by doing the same, but clicking Restart, instead. The power button on most laptops, and some desktops, is not configured to shut the machine down, but rather to sleep the machine. Sleeping the machine does not accomplish the same thing as shutting it down or restarting it. 

  • Uninstall any Killer Performance Suite and Killer Drivers entries in your Apps & Features menu
  • Restart your machine
  • Run the installer package that you just downloaded
  • Restart your machine once more

You should now have the latest drivers, and the latest Performance Suite installed. This should resolve any issues with VPN clients connecting. Please let us know if this does not solve your issue.

Problems With The Killer Network Manager


The Killer Network Manager is our outgoing performance suite. It is no longer being updated, and does not contain the latest Ethernet or Wi-Fi drivers. We encourage all users of the Killer Wireless-AC 1525/1535/1435, Killer Wireless-N 1202/1103, Killer E2200, Killer E2400, and Killer E2500 to upgrade to the Killer Control Center, found here - This includes users whose machines came with the Killer Network Manager preinstalled. There is no need to continue using the Killer Network Manager.

For a smooth installation, download the latest Killer Control Center installation package, then uninstall all Killer products from your Apps and Features menu, which is accessible by right-clicking Start, then restart your computer, and double-click the new installation package to install the new Killer Control Center.

The old Killer Network Manager suite is still available for download here - - but will no longer be updated, and may not be fully compatible with future Windows updates, antivirus suites, or other applications that manipulate network data.

Network Column in Windows Task Manager Not Working


For our software to display bandwidth correctly, Windows NDU (Windows Network Data Usage Monitoring Driver) ends up getting stopped/disabled. This is because both services work by examining packets, and both doing so at the same time can cause conflicts.

If you force NDU to run while Killer Control Center or Killer Network Manager is installed, those two programs may not display bandwidth correctly.

If you would like to re-activate the Windows NDU to test for yourself, open a Command Prompt and enter the following:

sc config ndu start=auto

After you enter that command, reboot your Computer.

NDU should now be set to start automatically and the Task Manager Processes tab should show traffic in the Network column, but the Killer Control Center or Killer Network Manager might not work properly.

To disable it, enter the following into a Command Prompt:

sc config ndu start=disabled

After you enter that command, reboot your Computer.

Memory Leaks


Some users have reported memory leaks with some versions of our performance suite. The current version of the Killer Control Center has no known instance of memory leaks. Unfortunately, when a computer is assembled, the software that is installed on the computer will not necessarily be up to date when the user unboxes the machine. This means that the user will need to update the software. Various computer manufacturers test and provide various versions of our software on their own support pages at their discretion, so the version of our software that you might find elsewhere on the web may not be the most up to date. If you are experiencing memory leaks, we highly suggest downloading and running the latest Killer Control Center installation package direclty from us, from this location - If you experience any memory leaks, or any other issues with the latest Killer Control Center, please reach out to us at the contact information below. 

Game Will Not Launch Due To BfLLR.DLL

Some users may encounter an error where games are unable to launch due to BfLLR.DLL being blocked.
The issue is that the anticheat mechanism used by some games is erroneously blocking certain .DLL files used by various applications that are in no way related to cheating. BfLLR.DLL is currently one of those files. Ultimately, the fix should come from the anticheat software engineers fixing this faulty behavior.
If you are using the Killer E2200, or any of our wireless adapters, and it came preinstalled with the Killer Network Manager, you can update to the new Killer Control Center instead of the Killer Network Manager. The Killer Control Center does not use BfLLR.DLL. You can use these steps to remove the Killer Network Manager, and install the Killer Control Center. 
  1. Download the latest Killer Control Center installation package from here -
  2. Download the Killer Software Uninstaller -
  3. Restart your computer by clicking Start > Power > Restart to free up as many in-use files as possible.
  4. Disable or temporarily uninstall any antivirus application you may be running. This is important as antivirus programs may prevent the .DLL from being removed.
  5. Run the Killer Software Uninstaller, and click Remove Killer Software. It will say REBOOT REQUIRED when it is finished.
  6. Restart your computer by clicking Start > Power > Restart.
  7. Right-click Start, and click Apps and Features
  8. Check for the Killer Network Manager, and any other application with "Killer" in it, including anything mentioning "Killer Drivers" or "Killer Suite," click it, and click Uninstall. If your computer prompts you to restart, make sure you restart before returning to the Apps and Features menu and removing any other "Killer" applications. You may find nothing at all, which means the Killer Software Remover Tool already removed everything.
  9. Once you have removed the last application, restart by clicking Start > Power > Restart
  10. Once the machine has restarted, verify that C:\Windows\System32\BfLLR.DLL is no longer present. You may need to show hidden files in this folder by clicking View and putting a check in the box for Hidden Items. If the file is still present, set a system restore point ( and then manually delete the BfLLR.dll.
  11. If you are unable to delete the BfLLR.DLL file even with no antivirus program installed, you may have to do it from safe mode -
  12. Once BfLLR.DLL is no longer on your drive, install the new Killer Control Center that you downloaded, which will contain the latest performance suite and drivers for your Ethernet adapter.

If you are unable to delete the BfLLR.DLL file, or if you have any other issues with a Killer product, please feel free to reach out to us for further assistance. 

Have a question about your Killer product that isn't answered in our Knowledge Base?  Contact Us.