I discovered this problem when trying to use the firewall in Avast Premier. I do not remember when I had a virus, but I did some time ago, and I thought I had cleaned up -- but now I realized my firewall would not start. I received the error code 0x80070424. I spent two weekends trying to fix this. I got as far as realizing that some of my services (BFE and Windows Firewall) would not start. I googled all over the place and found little to help, but did find suggestions to fix the registry. None that I tried worked. On the third weekend, I found BleepingComputer's site, and downloaded Windows Repair (All in One). It suggested a clean boot, and gave instructions. It also recommended using MalwareBytes Anti-Malware first, which I had already downloded and run, but ran again with no issues found. Then I followed the easy instructions for Windows Repair (All in One.) I unchecked the items for Windows 8, since I am on 7, but basically used the defaults. My problem is solved!! This was wonderful, and I wanted to recommend it if you are finding error code 0x80070424.and there are problems starting the Windows Firewall service. Yay!! I'm happy now and thought I should share with others that may be having this issue. I am not technically savvy enough to have tackled fixing the registry by myself. I have had no issues since I ran this application.