Update KB2961072 failed error code 800B0100

Open an Elevated Command Prompt, and run the following command

NETSH WINSOCK /RESET

reboot on request and see if that helps.

If not, check Device Manager, and see if there are any errors showing there - make sure that you enable the 'Show Hidden devices' option in the View menu bar option.

I'll ask someone else to have a look - I don't profess to being a networking expert.

Someone will post back to this thread - soon, hopefully! - who has as much knowledge as you'd get from posting there.
Hang tight!

I had the exact same problem as this with my computer. After trying everything I eventually found that after installing KB2961072 the afd.sys file was showing as not digitally signed. (After running sigverif.exe at an elevated command prompt). Note: sfc /scannow showed no errors

Also in device manager (after showing hidden devices is selected) in Non-Plug and play drivers, the "Ancillary Function Driver for Winsock" was showing as this driver is not digitally signed and cannot be started.

The digital signatures stored in the catalogue files for afd.sys were obviously corrupted. I deleted the existing versions of the following files in the directory shown and then re-run the standalone installer for KB2961072 (Windows6.1-KB2961072-x64.msu) and the update installed and the internet worked again.

C:\Windows\System32\catroot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}\Package_2_for_KB2961072~31bf3856ad364e35~amd64~~6.1.1.1.cat


C:\Windows\System32\catroot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}\Package_for_KB2961072_SP1~31bf3856ad364e35~amd64~~6.1.1.1.cat


C:\Windows\System32\catroot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}\Package_for_KB2961072_SP1~31bf3856ad364e35~amd64~~6.1.1.1.cat


.

Thanks for that - Did you run CheckSUR at all? It should have picked up the CAT file corruption and pointed it out.

Did you actually look at the log file it produced? It doesn't tell you anything about what it found unless you do (bad design, to my mind!)