code 31 on network adapters,

[SwissJim]

Windows 8.1 on an HP m6-n010dx.

Note: I've already tried:

- Restoring the system to a backup from before all this happened.

- Updating the drivers

- The workaround at https://support.microsoft.com/en-gb/help/2871372/code-31-error-in-device-manager-for-wan-miniport-ne.... The update to Microsoft KM-TEST Loopback Adapter, or to any other driver in the list, fails with the same code 31 error.

- Deleting the config subkey in the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network, and rebooting. All the same network adapters still had the code 31 error.

Following a failed install, and an uninstall, of a VPN app, some network adapters on my wife's computer are reported as not working properly because Windows can not find the required drivers. Which ones work and which ones don't has changed a few times, following my failed efforts to fix them. At first it was the Tap adapter and all the hidden WAN miniport adapters that were not working, all the time. Then I accidentally got the Tap adapter working by installing an older version of my other VPN app. Then it was only the SSTP adapter that was not working, all the time, and the other WAN miniport adapters showed exclamation marks only when my other VPN app was trying to connect with any one of them. Then I tried updating my wifi adapter, and afterwards that stopped working, with code 31. I've tried the method of updating the adapter driver with the Microsoft KM Loopback adapter, to uninstall it, and that installation fails with the same code 31. At one point I tried restoring the system to a backup from before this all happened, but after the restore the adapters still had the same code 31 error.

At one point I deleted some registry entries that referred to my VPN services, but the backup that I used to restore the system after that, was from before any of this happened, and after the restore, the adapters were still not working.

One solution that was proposed by the provider of the VPN app that failed to install, was to try disabling driver signature enforcement. I haven't tried that because my wife and I have identical computers with the latest Windows 8.1 updates on both of them, and I'm not having any problem with the adapters on mine, so a problem with driver signatures doesn't seem like a possible explanation to me.

(edited to add the following)

I found a possible new lead. I looked through the recent events in the events viewer, and found some RasMan events which say that the Remote Access Communication Manager failed to start because it could not load one or more communication DLLs.

One person solved this problem by re-installing the Windows 8.1 update: https://social.technet.microsoft.com/Forums/lync/en-US/fb247712-93a4-4206-bfd7-ea696f9eb561/remote-a...

[SwissJim]

Now I'm reading rasman.dll from the Windows system32 folder, to see what dll's it uses. Then I'll check to see if any of those are missing or corrupted.