Fix NERR_CfgParamNotFound (0X00000863) in Windows

Most common cause: A corrupted registry key from a failed Windows update or driver install

In my ten years running a help desk, I've seen this error pop up most often after a Windows update fails mid-install, or when a network adapter driver gets partially removed. The system can't find a parameter it expects in the registry, so it throws 0X00000863. You might see this when opening Network Connections or trying to configure a VPN or a direct cable connection.

Here's what you'll see: You open ncpa.cpl, and instead of your network adapters, you get a popup saying "The specified parameter could not be found in the configuration information." Or you're setting up a new connection in Control Panel, and it fails with the same message.

The fix is to repair the registry key that stores network configuration parameters. I'm going to give you the exact steps I've used on dozens of machines running Windows 10 22H2 and Windows 11 23H2.

1. Press Windows Key + R to open the Run dialog.
2. Type regedit and hit Enter. Click Yes if UAC asks for permission.
3. In the Registry Editor, go to this path:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters

4. Look on the right side for a value named Size. It should be a DWORD (32-bit). If it's missing, that's your problem. Don't panic — many machines have this missing and still work fine, but when it's corrupted from an update, the kernel can't read it.
5. Right-click an empty space in the right pane, choose New > DWORD (32-bit) Value. Name it Size.
6. Double-click Size, set the value data to 1. The base should be Hexadecimal. Click OK.
7. Close Registry Editor.
8. Restart your computer. After the restart, try opening Network Connections again. The error should be gone.

What to expect: After restarting, when you open ncpa.cpl, you'll see your network adapters listed. If you still get the error, move on to the next cause.

Second most common cause: Corrupted network configuration cache (the "NetworkList" key)

Sometimes the problem isn't the LanmanServer key but the cached list of network profiles. Windows stores these in a different registry location. A failed network profile migration (from a domain to workgroup, for example) can corrupt this cache.

You'll know this is your issue if the error shows up when you're trying to browse network shares or when the Network icon in the system tray shows "Unidentified network" even though you have internet access.

1. Open Registry Editor again (Win+R, type regedit, hit Enter).
2. Navigate to:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList

3. Right-click the NetworkList key and choose Export. Save it somewhere as a backup (in case something goes sideways).
4. Now, delete the Profiles subkey inside NetworkList. To be clear: right-click Profiles and choose Delete. Confirm Yes.
5. Also delete the Signatures subkey under NetworkList. Same process.
6. Close Registry Editor.
7. Open an elevated Command Prompt (right-click Start, choose Terminal (Admin) or Command Prompt (Admin)).
8. Type ipconfig /flushdns and press Enter. You should see "Successfully flushed the DNS Resolver Cache."
9. Then type netsh int ip reset and press Enter. Wait for it to complete.
10. Finally, type shutdown /r /t 0 to restart immediately.

What to expect: After restarting, Windows will rebuild the network profiles from scratch. Your network connections will show as "Public" at first. That's normal. You can change them back to Private through Settings > Network & Internet > Properties. The error should be gone.

One warning here: If you're on a domain-joined machine, deleting those keys can cause group policy network settings to fail temporarily. They'll reapply on the next group policy refresh (usually every 90 minutes). For a home machine, no worries.

Third cause: Missing or corrupted network service dependencies

This one is rarer, but I've seen it on machines where someone disabled services to "speed up" Windows. The Network Location Awareness (NLA) service or the TCP/IP NetBIOS Helper service might be stopped or set to Manual when they should be running.

The 0X00000863 error can show up in Event Viewer under System logs with source "NETLOGON" or "Service Control Manager" event ID 7001.

1. Press Win+R, type services.msc, hit Enter.
2. Scroll down to Network Location Awareness. Double-click it.
3. Set the Startup type to Automatic (Delayed Start). Click Apply, then click Start.
4. Find TCP/IP NetBIOS Helper. Double-click it.
5. Set Startup type to Automatic. Click Apply, then Start.
6. Find Server service. Double-click it. Set Startup type to Automatic, Apply, then Start.
7. Close Services.
8. Open Command Prompt as admin. Run sfc /scannow. Let it finish completely — this can take 15 minutes.
9. After sfc, run DISM /Online /Cleanup-Image /RestoreHealth. This takes 15-20 minutes. Don't interrupt it.
10. Restart your computer.

What to expect: After the restart, all network services will be running with correct startup types. The error should vanish. If you still see it, you might have a deeper issue like a third-party firewall or antivirus blocking network parameter access. Temporarily disable them to test.

Quick-reference summary table

One last thing: if none of these work, check if you recently installed any VPN software like Cisco AnyConnect or Pulse Secure. Those are notorious for mangling the network configuration registry. Uninstalling them and using their cleanup tool (usually available on the vendor's site) often resolves the 0X00000863 error.

You've got this. Walk through the steps in order, and you'll have it fixed inside an hour.