How To Resolve the Windows Firewall Settings Error 0x8007042c

Dealing with error 0x8007042c when turning on the Windows Firewall can be a huge headache. Basically, it means some firewall services aren’t starting properly, which stops you from locking down your network as you should. Sometimes, it’s just because the Base Filtering Engine (BFE) or the Windows Defender Firewall service has decided to stop working—maybe after a Windows update, or because some rogue third-party security app is messing with things. No surprise, but interference from antivirus software or corrupted DLL files can also throw a wrench in the works. If you’re landing on this error, fixing it means poking around in services, resetting some DLLs, or making sure your security setup isn’t shot to hell.

How to Fix Error 0x8007042c and Get the Firewall Back in Action

Ensure Firewall Services Are Running Properly

This fixes a common root cause: services being stopped or disabled. If these aren’t running, Windows Firewall basically can’t do its job, so gotta get them started and set to auto. When these services run fine, Windows can manage your firewall rules again without giving you the “can’t change settings” error.

  1. Hit Win + R to open the Run dialog.
  2. Type services.msc and press Enter or click OK. This opens the Services window.
  3. Find Base Filtering Engine, double-click it to open properties.
  4. Make sure Startup type is set to Automatic. If the service shows as stopped, click Start. Don’t forget to click Apply and then OK.
  5. Repeat the same for Windows Defender Firewall. Ensure it’s also set to Automatic and running.
  6. Close the services window and see if turning the firewall on works now. Sometimes this fixes it outright, but if the error persists, move on.

Re-register Firewall DLL Files to Fix Missing or Corrupted Entries

Because Windows relies on those DLL files to keep the firewall running smoothly, re-registering them can sometimes fix mysterious errors—especially if files got corrupted or went missing. Why does this help? Well, re-registering resets some registry entries, forcing Windows to recognize the right DLLs and enable the firewall again.

  1. Open the Start Menu, type cmd.
  2. Right-click on Command Prompt and choose Run as administrator. This step is crucial—admin rights are mandatory here.
  3. In the black window, run these commands one after another (press Enter after each): 
    regsvr32 firewallapi.dll regsvr32 hnetcfg.dll regsvr32 netshell.dll regsvr32 netcfgx.dll regsvr32 netman.dll
  4. Watch the success or failure messages. Usually, you’ll get a confirmation that the DLL registered successfully. If any tell you it failed, that might be a clue to more underlying issues.
  5. Once done, restart your PC and see if the firewall error sticks around or not.

Get Rid of Conflicting Third-Party Antivirus Software

Often, leftover or incompatible third-party antivirus tools end up blocking the Windows Firewall or stopping its services altogether. If you’re running any other security software, try uninstalling it temporarily to see if that restores normal firewall function. Some antivirus tools disable Windows Defender or firewall services outright, and even after uninstalling, remnants can keep things from working. In that case, a proper cleanup tool or manual removal via the control panel might be needed, but sometimes just turning off or uninstalling does the trick.

  1. Open the Control Panel by typing appwiz.cpl in the Run box (Win + R).
  2. Find your antivirus in the list, double-click, or right-click and select Uninstall.
  3. Follow the prompts to remove it cleanly. After that, restart your system.
  4. Try turning the Windows Firewall on again—fingers crossed it’s fixed now.

Reset Firewall Settings to Default

If the rules or policies got all screwed up, resetting the firewall might wipe away the bad conf—kind of like a fresh start. This can fix errors caused by incorrect rules or rogue policies that prevent the firewall from starting properly.

  1. Open Control Panel again via control or Win + R, then go to System and Security > Windows Defender Firewall.
  2. Click on Restore Defaults on the left sidebar.
  3. Click Restore Defaults again, and wait for the process to finish. It may take a moment.
  4. Close out and try re-enabling the firewall.

If after all that, the firewall still refuses to turn on, running an sfc /scannow scan in an elevated Command Prompt can help fix corrupted system files, including those related to Windows Security components. Just remember, this might take some time, and you’ll need to reboot afterward to see if things improve.

And if nothing works, sometimes the only options left are restoring from a backup or resetting Windows. Not ideal, but it’s a last resort to get control back over your system’s security.

Summary

  • Check if Base Filtering Engine and Firewall services are running. Set them to Automatic.
  • Re-register Windows Firewall DLLs using Command Prompt as admin.
  • Uninstall or disable any third-party security apps causing conflicts.
  • Reset firewall rules to default if things are all jacked up.
  • Run sfc /scannow to fix potential system file corruption.

Wrap-up

This stuff can be a pain, but fixing the firewall usually comes down to making sure services are running, DLL files are registered properly, and there’s no security app messing everything up. Sometimes, a simple restart or DLL re-register is enough. For others, clean installs or resetting Windows are the final options. Fingers crossed this helps someone save hours of frustration—and gets that firewall working again.

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