You must have Hyper-V enabled. If you are on Windows 11 Pro or Enterprise, you can enable it via Control Panel > Programs > Turn Windows features on or off > Hyper-V .
Here are the methods for both.
(if not already)
Open and run:
Complete Guide: How to Add a Virtual Network Adapter in Windows 11 add virtual network adapter windows 11
Adding a virtual network adapter in Windows 11 allows you to simulate a network connection without needing physical hardware. This is essential for developers testing local servers, IT professionals managing virtual machines, or users needing to isolate network traffic. You must have Hyper-V enabled