You will often see and TUN mentioned together. While they are similar, they operate at different layers of the network model:
This error means the driver is stuck or another VPN is hogging the adapter.
TAP-Windows acts as a virtual network interface card (NIC). When you connect to a VPN, the TAP driver "picks up" your internet traffic before it leaves your physical Wi-Fi or Ethernet card. It encrypts this traffic and sends it through a secure "tunnel" to the VPN server.
is an essential but invisible component that enables VPNs and virtual networking on Windows. It provides a virtual Ethernet card that software can use to intercept, encrypt, and redirect network traffic. While most users never need to interact with it directly, understanding tap-windows helps diagnose VPN connection issues and appreciate how modern software-defined networking works on the Windows platform.