The Microsoft TUN Miniport Adapter is a built-in part of Windows networking architectures. This device is designed to handle the tunneling or bridging between network devices. Microsoft developed this miniport to support the new Internet Protocol version 6 (IPv6) technologies. The Microsoft TUN Miniport Adapter is the component that supports TUN devices.
Miniport adapters manage the network interface cards (NIC) and the communication with the higher-level drivers. Miniports are virtual devices, not real hardware devices that can be removed from the computer. These pieces of network software are created when a virtual network is formed through remote access or through peer-to-peer communications with remote devices. Miniport adapters are written to the device manager through Windows updates.
Internet Protocol version 6 (IPv6) is the new standard protocol for the Internet. Internet protocols provide virtual addresses for computer and devices that connect to the Internet. These devices communicate using IP. IPv4, which is the prior IP, provides only 4 billion IP addresses, while IPv6 uses an unlimited number of IP addresses. IPv6 is designed for device mobility and auto-configuration. Support for IPv6 is built into Windows 7 and 2008.
A yellow exclamation point over the Microsoft TUN Miniport Adapter in the Device Manager means that the driver for the adapter is installed incorrectly. There may be no obvious problems to the operating system, because of the newness of the Miniport device and IP. Open the New Hardware Wizard and select the malfunctioning TUN adapter device. Follow the steps in the Troubleshooting Wizard and select a compatible TUN adapter from the list. Updating the Microsoft TUN Miniport Adapter driver does not repair the Miniport device.
When the computer’s network does not work and the Microsoft TUN Miniport Adapter is the suspect, then disable or uninstall the adapter. Start by uninstalling the IPv6, which locks the Microsoft TUN Miniport Adapter into the list of necessary programs, in the Control Panel. Look for the Network Connections and right-click on any network adapter. Choose “Local Area Connection” and click on “Properties.” Highlight “Microsoft TCP/IP version 6” and click “Uninstall.” Restart the computer, and then uninstall the Microsoft TUN Miniport Adapter in the Device Manager.