Network Protocols are a set of rules or standards used by Windows to communicate over the internet. They make sure the data is sent correctly across between computers, but if any of the Network Protocol is missing in Windows 10, things go south. You might not be able to browse the internet, share files. If the word protocol is still not clear, some examples are TCP, LLDP, etc.
One or more Network Protocols are missing on this computer
If after you run the Incoming Connections Troubleshooter, you receive any error which has a “Network Protocol is missing” message, below is a list of troubleshooting tips to use. You will need admin privileges to execute the commands.
1] Run Network troubleshooters
Windows 10 has multiple Network Troubleshooters which solve most of the problems related with the network. See if running any other troubleshooter helps you fix the issue.
2] Reinstall Network Adapter & Reset networking component
Sometimes corrupted driver cause issue, and the best way to go ahead is to reinstall network adapter. Open Device Manager, find your adapter, and then follow the instructions to reinstall and reset network adapters.
3] Diagnose Network Adapter
Go to Control Panel > All Control Panel Items > Network Connections and find the network adapter which might be causing the problem. If you are using WiFi, then it’s your WiFi adapter, else it’s your Ethernet adapter. Right-click and select diagnose to troubleshoot.
4] Reset Winsock & TCP/IP
Windows Sockets or Winsock is like socket which was initially designed to add support for IPv4 to Windows. Later this evolved to support more protocol. It is possible to reset Winsock with the following command “netsh winsock reset.” Open the Command Prompt with admin privileges, and then execute the command.
You may want to also Reset TCP/IP.
5] Import Winsock settings from another computer
If the reset Winsock attempt doesn’t work, you can import settings from a computer on which there is no network protocol error. To get this done, you will have to access the registry, and then export and import few settings. So make sure you know how to handle registry.
Type regedit in the Command Prompt and hit enter.
In the registry hive, navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
Find two keys (they look like folders) with name Winsock and Winsock2. Right-click on each of them, and select Export.
Copy the registry keys to a USB drive. Next, copy the keys on the PC where the network protocol issue exists.
Now double-click on each of them, and it will install the WINSOCK keys.
We also recommend you to check out detailed guide of Network troubleshooting in Windows 10. It has a list of all possible commands that you can use to fix networking issues in Windows 10.