Error code 0x80070424 (or 0x80070422) occuring when trying to enable the Windows Firewall, or Defender usually indicates the presence of a trojan/rootkit on a 64-bit Windows 7/Vista.
The key to resolving this issue is cleaning the rootkit/virus from your computer.
One of the most widely spread rootkits, and a likely cause is the Zero Access Rootkit , a.k.a. Win32:Sirefef
You can confirm its presence by looking for the following folder:
C:/WINDOWS/SYSTEM64 (not the sysWOW64)
and the following file:
C:/WINDOWS/SYSTEM32/CONSRV.DLL
First, try to clean the rootkit, you can use one of the following tools:
ESET Sirefef (ZeroAccess) Cleaner Tool McAfee Rootkit RemoverOnce your system is cleaned up, you should run a full scan with a reputable recent Antivirus program, and install Windows Security updates. It is also a good idea to run the rootkit removal tools again after a reboot to verify that they do not find the same issue and were able to clean it successfully.
Below is a short list of some free Antivirus/Antimalware programs we recommend. Please note you should only run one antivirus program, as they may interfere with each other. You can, however, install both antivirus and anti-spyware software, as long as you only leave one running.
Microsoft Security EssentialsBitdefender Antivirus FreeAvast! Free AntivirusMalwarebytes Anti-Malware Free
