Microsoft Loopback Adapter (officially renamed to Microsoft KM-TEST Loopback Adapter

Open Command Prompt and run:

: Scroll down, select Network adapters , and click Next . Select Manufacturer : Under Manufacturer , select Microsoft . Under Model , select Microsoft KM-TEST Loopback Adapter .

in newer versions) is a virtual networking tool that simulates a network connection. It allows you to test network-dependent software on your Windows 11 machine even when you aren't connected to a physical network. How to Install the Loopback Adapter on Windows 11