How to reset / reinstall the networking on Windows 7

You want to use the "Change Adapter Settings" link then look at the properties of all of the physical adapters (connected and disconnected), you will also see the virtual adapters - don't change these unless you need to.

In each NIC you will see one or more line items for the virtual adapters. Enable or Disable as needed - for instance if you never use the wired NIC you can disable the virtual adapter for that device.

Unexplainable loss of network connectivity, usually via wired and wireless (wifi) networking Windows 7 for some reason needs to be system restored to the last working configuration, I've seen this happen on several pc's - Dell and Lenovo. Once customers roll back the network starts working again, and from that point on works without difficulty. No network stack resets or driver updates resolved this.