Unable to turn on Windows Firewall: Error code 0x6D9

Hi Seattle Swede,

Did you check if Windows Firewall service is running?

Windows firewall in Windows 7 relies on the following two services. In other words, these are the dependency services for Windows Firewall.

1. Base Filtering Engine (BFE)
2. Windows Firewall Authorization Driver (MPSDRV)

If these two services are running, then by default Windows Firewall Service should run. I know you’ve tried enough steps to turn on Windows Firewall, but I would ask you to follow these steps to check if it fixes the issue.

a.    Open a Command Prompt as Administrator. To do this, type CMD in Start Search from the Start Menu. Right click on the result and choose "Run as Administrator".

b.    Run the following command lines:
          1. netsh advfirewall reset
          2. net start mpsdrv
          3. net start bfe
          4. net start mpssvc
          5. regsvr32 firewallapi.dll

c.    Confirm any boxes that comes up by clicking OK. The result on the last entry should say that  it succeeded.
      Note: If you receive any errors on any of the command lines, then there is definitely something wrong with any of the drivers and service.
              This may indicate a Registry error or a Corrupted file.

d.    Reboot the system.

Now check if you’re able to turn on Windows firewall.

Hope this information is helpful and let me know if you need any further assistance.

Mouneshwar R – Microsoft Support

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