Microsoft Loopback Adapter Driver

The Microsoft Loopback Adapter is a virtual network adapter used to test network configurations and support software that needs a network interface without a physical connection. Its Microsoft driver lets Windows recognize and configure the adapter, making it useful for local development, troubleshooting, and isolated test setups.

Key Features

• Virtual network interface: Provides a software-based adapter without requiring an Ethernet card, Wi-Fi connection, or attached network cable.
• Configurable IP settings: Supports manual IP address and subnet configuration for applications and services that need a stable local network interface.
• Network testing support: Helps developers and administrators check application behavior and experiment with network settings without changing a physical adapter’s configuration.
• Built-in Windows integration: Uses Microsoft’s Windows networking components and can be managed through Device Manager and network adapter settings. On newer Windows versions, it is typically listed as the Microsoft KM-TEST Loopback Adapter.

How to Install

1. Check your Windows version. The adapter is available through Windows’ built-in hardware installation tools on Windows 11, 10, 8, and 7. The displayed device name may differ between versions; a separate driver download is usually unnecessary.

1. Launch the hardware wizard. Press Windows + R, enter `hdwwiz`, and press Enter. Approve the administrator prompt if requested, then select Next to begin.

1. Choose manual installation. Select “Install the hardware that I manually select from a list (Advanced).” Choose Network adapters from the hardware categories and continue.

1. Select the Microsoft adapter. Under Manufacturer, choose Microsoft. Select Microsoft KM-TEST Loopback Adapter, or Microsoft Loopback Adapter if that is the name shown in your Windows version. Follow the prompts to complete installation.

1. Verify and configure the interface. Open Device Manager and check that the adapter appears under Network adapters without a warning symbol. If your test environment requires a fixed address, open the adapter’s IPv4 properties in Network Connections and enter the appropriate IP address and subnet mask.

This virtual adapter does not provide internet access by itself or replace the driver for a physical network card. If you are troubleshooting Ethernet or Wi-Fi connectivity, check the driver for that hardware instead.